Refactored query engine utilizing iterators

Makefile

@@ -51,6 +51,10 @@ build-sharedlib-linux-amd64:
 	@echo "Building shared library for Linux x64..."
 	@GOOS=linux GOARCH=amd64 $(GOBUILD) $(SHARED_LIB_OPT) -o $(DIST_DIR)/$(BINARY_NAME)-linux-amd64.so $(SHARED_LIB_LOCATION)
 
+build-sharedlib-darwin-arm64:
+	@echo "Building shared library for macOS ARM..."
+	@GOOS=darwin GOARCH=arm64 $(GOBUILD) $(SHARED_LIB_OPT) -o $(DIST_DIR)/$(BINARY_NAME)-darwin-arm64.so $(SHARED_LIB_LOCATION)
+
 build-sharedlib-tests: build-sharedlib-linux-amd64
 	@echo "Building shared library tests..."
 	@$(SHARED_LIB_TEST_CC) $(SHARED_LIB_TEST_CFLAGS) -o $(SHARED_LIB_TEST_TARGET) $(SHARED_LIB_TEST_SOURCES)

api/api_server.go

@@ -3,7 +3,7 @@ package api
 import (
 	"github.com/gin-gonic/gin"
 	"github.com/pikami/cosmium/api/config"
-	"github.com/pikami/cosmium/internal/repositories"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 type ApiServer struct {
@@ -14,7 +14,7 @@ type ApiServer struct {
 	config           *config.ServerConfig
 }
 
-func NewApiServer(dataRepository *repositories.DataRepository, config *config.ServerConfig) *ApiServer {
+func NewApiServer(dataStore datastore.DataStore, config *config.ServerConfig) *ApiServer {
 	stopChan := make(chan interface{})
 	onServerShutdownChan := make(chan interface{})
 
@@ -24,7 +24,7 @@ func NewApiServer(dataRepository *repositories.DataRepository, config *config.Se
 		config:           config,
 	}
 
-	apiServer.CreateRouter(dataRepository)
+	apiServer.CreateRouter(dataStore)
 
 	return apiServer
 }

api/handlers/collections.go

@@ -5,15 +5,15 @@ import (
 	"net/http"
 
 	"github.com/gin-gonic/gin"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 func (h *Handlers) GetAllCollections(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 
-	collections, status := h.repository.GetAllCollections(databaseId)
-	if status == repositorymodels.StatusOk {
-		database, _ := h.repository.GetDatabase(databaseId)
+	collections, status := h.dataStore.GetAllCollections(databaseId)
+	if status == datastore.StatusOk {
+		database, _ := h.dataStore.GetDatabase(databaseId)
 
 		c.Header("x-ms-item-count", fmt.Sprintf("%d", len(collections)))
 		c.IndentedJSON(http.StatusOK, gin.H{
@@ -31,13 +31,13 @@ func (h *Handlers) GetCollection(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	id := c.Param("collId")
 
-	collection, status := h.repository.GetCollection(databaseId, id)
-	if status == repositorymodels.StatusOk {
+	collection, status := h.dataStore.GetCollection(databaseId, id)
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, collection)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -49,13 +49,13 @@ func (h *Handlers) DeleteCollection(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	id := c.Param("collId")
 
-	status := h.repository.DeleteCollection(databaseId, id)
-	if status == repositorymodels.StatusOk {
+	status := h.dataStore.DeleteCollection(databaseId, id)
+	if status == datastore.StatusOk {
 		c.Status(http.StatusNoContent)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -65,7 +65,7 @@ func (h *Handlers) DeleteCollection(c *gin.Context) {
 
 func (h *Handlers) CreateCollection(c *gin.Context) {
 	databaseId := c.Param("databaseId")
-	var newCollection repositorymodels.Collection
+	var newCollection datastore.Collection
 
 	if err := c.BindJSON(&newCollection); err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"message": err.Error()})
@@ -77,13 +77,13 @@ func (h *Handlers) CreateCollection(c *gin.Context) {
 		return
 	}
 
-	createdCollection, status := h.repository.CreateCollection(databaseId, newCollection)
-	if status == repositorymodels.Conflict {
+	createdCollection, status := h.dataStore.CreateCollection(databaseId, newCollection)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdCollection)
 		return
 	}

api/handlers/cosmium.go

@@ -7,11 +7,11 @@ import (
 )
 
 func (h *Handlers) CosmiumExport(c *gin.Context) {
-	repositoryState, err := h.repository.GetState()
+	dataStoreState, err := h.dataStore.DumpToJson()
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
 		return
 	}
 
-	c.Data(http.StatusOK, "application/json", []byte(repositoryState))
+	c.Data(http.StatusOK, "application/json", []byte(dataStoreState))
 }

api/handlers/databases.go

@@ -5,12 +5,12 @@ import (
 	"net/http"
 
 	"github.com/gin-gonic/gin"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 func (h *Handlers) GetAllDatabases(c *gin.Context) {
-	databases, status := h.repository.GetAllDatabases()
-	if status == repositorymodels.StatusOk {
+	databases, status := h.dataStore.GetAllDatabases()
+	if status == datastore.StatusOk {
 		c.Header("x-ms-item-count", fmt.Sprintf("%d", len(databases)))
 		c.IndentedJSON(http.StatusOK, gin.H{
 			"_rid":      "",
@@ -26,13 +26,13 @@ func (h *Handlers) GetAllDatabases(c *gin.Context) {
 func (h *Handlers) GetDatabase(c *gin.Context) {
 	id := c.Param("databaseId")
 
-	database, status := h.repository.GetDatabase(id)
-	if status == repositorymodels.StatusOk {
+	database, status := h.dataStore.GetDatabase(id)
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, database)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -43,13 +43,13 @@ func (h *Handlers) GetDatabase(c *gin.Context) {
 func (h *Handlers) DeleteDatabase(c *gin.Context) {
 	id := c.Param("databaseId")
 
-	status := h.repository.DeleteDatabase(id)
-	if status == repositorymodels.StatusOk {
+	status := h.dataStore.DeleteDatabase(id)
+	if status == datastore.StatusOk {
 		c.Status(http.StatusNoContent)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -58,7 +58,7 @@ func (h *Handlers) DeleteDatabase(c *gin.Context) {
 }
 
 func (h *Handlers) CreateDatabase(c *gin.Context) {
-	var newDatabase repositorymodels.Database
+	var newDatabase datastore.Database
 
 	if err := c.BindJSON(&newDatabase); err != nil {
 		c.JSON(http.StatusBadRequest, gin.H{"message": err.Error()})
@@ -70,13 +70,13 @@ func (h *Handlers) CreateDatabase(c *gin.Context) {
 		return
 	}
 
-	createdDatabase, status := h.repository.CreateDatabase(newDatabase)
-	if status == repositorymodels.Conflict {
+	createdDatabase, status := h.dataStore.CreateDatabase(newDatabase)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdDatabase)
 		return
 	}

api/handlers/documents.go

@@ -10,17 +10,21 @@ import (
 	"github.com/gin-gonic/gin"
 	apimodels "github.com/pikami/cosmium/api/api_models"
 	"github.com/pikami/cosmium/internal/constants"
+	"github.com/pikami/cosmium/internal/converters"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/logger"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/parsers"
+	"github.com/pikami/cosmium/parsers/nosql"
+	memoryexecutor "github.com/pikami/cosmium/query_executors/memory_executor"
 )
 
 func (h *Handlers) GetAllDocuments(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
 
-	documents, status := h.repository.GetAllDocuments(databaseId, collectionId)
-	if status == repositorymodels.StatusOk {
-		collection, _ := h.repository.GetCollection(databaseId, collectionId)
+	documents, status := h.dataStore.GetAllDocuments(databaseId, collectionId)
+	if status == datastore.StatusOk {
+		collection, _ := h.dataStore.GetCollection(databaseId, collectionId)
 
 		c.Header("x-ms-item-count", fmt.Sprintf("%d", len(documents)))
 		c.IndentedJSON(http.StatusOK, gin.H{
@@ -39,13 +43,13 @@ func (h *Handlers) GetDocument(c *gin.Context) {
 	collectionId := c.Param("collId")
 	documentId := c.Param("docId")
 
-	document, status := h.repository.GetDocument(databaseId, collectionId, documentId)
-	if status == repositorymodels.StatusOk {
+	document, status := h.dataStore.GetDocument(databaseId, collectionId, documentId)
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, document)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -58,13 +62,13 @@ func (h *Handlers) DeleteDocument(c *gin.Context) {
 	collectionId := c.Param("collId")
 	documentId := c.Param("docId")
 
-	status := h.repository.DeleteDocument(databaseId, collectionId, documentId)
-	if status == repositorymodels.StatusOk {
+	status := h.dataStore.DeleteDocument(databaseId, collectionId, documentId)
+	if status == datastore.StatusOk {
 		c.Status(http.StatusNoContent)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -72,7 +76,7 @@ func (h *Handlers) DeleteDocument(c *gin.Context) {
 	c.IndentedJSON(http.StatusInternalServerError, gin.H{"message": "Unknown error"})
 }
 
-// TODO: Maybe move "replace" logic to repository
+// TODO: Maybe move "replace" logic to data store
 func (h *Handlers) ReplaceDocument(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
@@ -84,19 +88,19 @@ func (h *Handlers) ReplaceDocument(c *gin.Context) {
 		return
 	}
 
-	status := h.repository.DeleteDocument(databaseId, collectionId, documentId)
-	if status == repositorymodels.StatusNotFound {
+	status := h.dataStore.DeleteDocument(databaseId, collectionId, documentId)
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
 
-	createdDocument, status := h.repository.CreateDocument(databaseId, collectionId, requestBody)
-	if status == repositorymodels.Conflict {
+	createdDocument, status := h.dataStore.CreateDocument(databaseId, collectionId, requestBody)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdDocument)
 		return
 	}
@@ -109,8 +113,8 @@ func (h *Handlers) PatchDocument(c *gin.Context) {
 	collectionId := c.Param("collId")
 	documentId := c.Param("docId")
 
-	document, status := h.repository.GetDocument(databaseId, collectionId, documentId)
-	if status == repositorymodels.StatusNotFound {
+	document, status := h.dataStore.GetDocument(databaseId, collectionId, documentId)
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -160,19 +164,19 @@ func (h *Handlers) PatchDocument(c *gin.Context) {
 		return
 	}
 
-	status = h.repository.DeleteDocument(databaseId, collectionId, documentId)
-	if status == repositorymodels.StatusNotFound {
+	status = h.dataStore.DeleteDocument(databaseId, collectionId, documentId)
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
 
-	createdDocument, status := h.repository.CreateDocument(databaseId, collectionId, modifiedDocument)
-	if status == repositorymodels.Conflict {
+	createdDocument, status := h.dataStore.CreateDocument(databaseId, collectionId, modifiedDocument)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdDocument)
 		return
 	}
@@ -210,16 +214,16 @@ func (h *Handlers) DocumentsPost(c *gin.Context) {
 
 	isUpsert, _ := strconv.ParseBool(c.GetHeader("x-ms-documentdb-is-upsert"))
 	if isUpsert {
-		h.repository.DeleteDocument(databaseId, collectionId, requestBody["id"].(string))
+		h.dataStore.DeleteDocument(databaseId, collectionId, requestBody["id"].(string))
 	}
 
-	createdDocument, status := h.repository.CreateDocument(databaseId, collectionId, requestBody)
-	if status == repositorymodels.Conflict {
+	createdDocument, status := h.dataStore.CreateDocument(databaseId, collectionId, requestBody)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdDocument)
 		return
 	}
@@ -253,14 +257,15 @@ func (h *Handlers) handleDocumentQuery(c *gin.Context, requestBody map[string]in
 		queryParameters = parametersToMap(paramsArray)
 	}
 
-	docs, status := h.repository.ExecuteQueryDocuments(databaseId, collectionId, requestBody["query"].(string), queryParameters)
-	if status != repositorymodels.StatusOk {
+	queryText := requestBody["query"].(string)
+	docs, status := h.executeQueryDocuments(databaseId, collectionId, queryText, queryParameters)
+	if status != datastore.StatusOk {
 		// TODO: Currently we return everything if the query fails
 		h.GetAllDocuments(c)
 		return
 	}
 
-	collection, _ := h.repository.GetCollection(databaseId, collectionId)
+	collection, _ := h.dataStore.GetCollection(databaseId, collectionId)
 	c.Header("x-ms-item-count", fmt.Sprintf("%d", len(docs)))
 	c.IndentedJSON(http.StatusOK, gin.H{
 		"_rid":      collection.ResourceID,
@@ -283,9 +288,9 @@ func (h *Handlers) handleBatchRequest(c *gin.Context) {
 	for idx, operation := range batchOperations {
 		switch operation.OperationType {
 		case apimodels.BatchOperationTypeCreate:
-			createdDocument, status := h.repository.CreateDocument(databaseId, collectionId, operation.ResourceBody)
-			responseCode := repositoryStatusToResponseCode(status)
-			if status == repositorymodels.StatusOk {
+			createdDocument, status := h.dataStore.CreateDocument(databaseId, collectionId, operation.ResourceBody)
+			responseCode := dataStoreStatusToResponseCode(status)
+			if status == datastore.StatusOk {
 				responseCode = http.StatusCreated
 			}
 			batchOperationResults[idx] = apimodels.BatchOperationResult{
@@ -293,25 +298,25 @@ func (h *Handlers) handleBatchRequest(c *gin.Context) {
 				ResourceBody: createdDocument,
 			}
 		case apimodels.BatchOperationTypeDelete:
-			status := h.repository.DeleteDocument(databaseId, collectionId, operation.Id)
-			responseCode := repositoryStatusToResponseCode(status)
-			if status == repositorymodels.StatusOk {
+			status := h.dataStore.DeleteDocument(databaseId, collectionId, operation.Id)
+			responseCode := dataStoreStatusToResponseCode(status)
+			if status == datastore.StatusOk {
 				responseCode = http.StatusNoContent
 			}
 			batchOperationResults[idx] = apimodels.BatchOperationResult{
 				StatusCode: responseCode,
 			}
 		case apimodels.BatchOperationTypeReplace:
-			deleteStatus := h.repository.DeleteDocument(databaseId, collectionId, operation.Id)
-			if deleteStatus == repositorymodels.StatusNotFound {
+			deleteStatus := h.dataStore.DeleteDocument(databaseId, collectionId, operation.Id)
+			if deleteStatus == datastore.StatusNotFound {
 				batchOperationResults[idx] = apimodels.BatchOperationResult{
 					StatusCode: http.StatusNotFound,
 				}
 				continue
 			}
-			createdDocument, createStatus := h.repository.CreateDocument(databaseId, collectionId, operation.ResourceBody)
-			responseCode := repositoryStatusToResponseCode(createStatus)
-			if createStatus == repositorymodels.StatusOk {
+			createdDocument, createStatus := h.dataStore.CreateDocument(databaseId, collectionId, operation.ResourceBody)
+			responseCode := dataStoreStatusToResponseCode(createStatus)
+			if createStatus == datastore.StatusOk {
 				responseCode = http.StatusCreated
 			}
 			batchOperationResults[idx] = apimodels.BatchOperationResult{
@@ -320,10 +325,10 @@ func (h *Handlers) handleBatchRequest(c *gin.Context) {
 			}
 		case apimodels.BatchOperationTypeUpsert:
 			documentId := operation.ResourceBody["id"].(string)
-			h.repository.DeleteDocument(databaseId, collectionId, documentId)
-			createdDocument, createStatus := h.repository.CreateDocument(databaseId, collectionId, operation.ResourceBody)
-			responseCode := repositoryStatusToResponseCode(createStatus)
-			if createStatus == repositorymodels.StatusOk {
+			h.dataStore.DeleteDocument(databaseId, collectionId, documentId)
+			createdDocument, createStatus := h.dataStore.CreateDocument(databaseId, collectionId, operation.ResourceBody)
+			responseCode := dataStoreStatusToResponseCode(createStatus)
+			if createStatus == datastore.StatusOk {
 				responseCode = http.StatusCreated
 			}
 			batchOperationResults[idx] = apimodels.BatchOperationResult{
@@ -331,9 +336,9 @@ func (h *Handlers) handleBatchRequest(c *gin.Context) {
 				ResourceBody: createdDocument,
 			}
 		case apimodels.BatchOperationTypeRead:
-			document, status := h.repository.GetDocument(databaseId, collectionId, operation.Id)
+			document, status := h.dataStore.GetDocument(databaseId, collectionId, operation.Id)
 			batchOperationResults[idx] = apimodels.BatchOperationResult{
-				StatusCode:   repositoryStatusToResponseCode(status),
+				StatusCode:   dataStoreStatusToResponseCode(status),
 				ResourceBody: document,
 			}
 		case apimodels.BatchOperationTypePatch:
@@ -352,17 +357,39 @@ func (h *Handlers) handleBatchRequest(c *gin.Context) {
 	c.JSON(http.StatusOK, batchOperationResults)
 }
 
-func repositoryStatusToResponseCode(status repositorymodels.RepositoryStatus) int {
+func dataStoreStatusToResponseCode(status datastore.DataStoreStatus) int {
 	switch status {
-	case repositorymodels.StatusOk:
+	case datastore.StatusOk:
 		return http.StatusOK
-	case repositorymodels.StatusNotFound:
+	case datastore.StatusNotFound:
 		return http.StatusNotFound
-	case repositorymodels.Conflict:
+	case datastore.Conflict:
 		return http.StatusConflict
-	case repositorymodels.BadRequest:
+	case datastore.BadRequest:
 		return http.StatusBadRequest
 	default:
 		return http.StatusInternalServerError
 	}
 }
+
+func (h *Handlers) executeQueryDocuments(databaseId string, collectionId string, query string, queryParameters map[string]interface{}) ([]memoryexecutor.RowType, datastore.DataStoreStatus) {
+	parsedQuery, err := nosql.Parse("", []byte(query))
+	if err != nil {
+		logger.Errorf("Failed to parse query: %s\nerr: %v", query, err)
+		return nil, datastore.BadRequest
+	}
+
+	allDocumentsIterator, status := h.dataStore.GetDocumentIterator(databaseId, collectionId)
+	if status != datastore.StatusOk {
+		return nil, status
+	}
+
+	rowsIterator := converters.NewDocumentToRowTypeIterator(allDocumentsIterator)
+
+	if typedQuery, ok := parsedQuery.(parsers.SelectStmt); ok {
+		typedQuery.Parameters = queryParameters
+		return memoryexecutor.ExecuteQuery(typedQuery, rowsIterator), datastore.StatusOk
+	}
+
+	return nil, datastore.BadRequest
+}

api/handlers/handlers.go

@@ -2,17 +2,17 @@ package handlers
 
 import (
 	"github.com/pikami/cosmium/api/config"
-	"github.com/pikami/cosmium/internal/repositories"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 type Handlers struct {
-	repository *repositories.DataRepository
-	config     *config.ServerConfig
+	dataStore datastore.DataStore
+	config    *config.ServerConfig
 }
 
-func NewHandlers(dataRepository *repositories.DataRepository, config *config.ServerConfig) *Handlers {
+func NewHandlers(dataStore datastore.DataStore, config *config.ServerConfig) *Handlers {
 	return &Handlers{
-		repository: dataRepository,
-		config:     config,
+		dataStore: dataStore,
+		config:    config,
 	}
 }

api/handlers/partition_key_ranges.go

@@ -5,7 +5,7 @@ import (
 	"net/http"
 
 	"github.com/gin-gonic/gin"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/resourceid"
 )
 
@@ -18,8 +18,8 @@ func (h *Handlers) GetPartitionKeyRanges(c *gin.Context) {
 		return
 	}
 
-	partitionKeyRanges, status := h.repository.GetPartitionKeyRanges(databaseId, collectionId)
-	if status == repositorymodels.StatusOk {
+	partitionKeyRanges, status := h.dataStore.GetPartitionKeyRanges(databaseId, collectionId)
+	if status == datastore.StatusOk {
 		c.Header("etag", "\"420\"")
 		c.Header("lsn", "420")
 		c.Header("x-ms-cosmos-llsn", "420")
@@ -27,7 +27,7 @@ func (h *Handlers) GetPartitionKeyRanges(c *gin.Context) {
 		c.Header("x-ms-item-count", fmt.Sprintf("%d", len(partitionKeyRanges)))
 
 		collectionRid := collectionId
-		collection, _ := h.repository.GetCollection(databaseId, collectionId)
+		collection, _ := h.dataStore.GetCollection(databaseId, collectionId)
 		if collection.ResourceID != "" {
 			collectionRid = collection.ResourceID
 		}
@@ -41,7 +41,7 @@ func (h *Handlers) GetPartitionKeyRanges(c *gin.Context) {
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}

api/handlers/stored_procedures.go

@@ -5,16 +5,16 @@ import (
 	"net/http"
 
 	"github.com/gin-gonic/gin"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 func (h *Handlers) GetAllStoredProcedures(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
 
-	sps, status := h.repository.GetAllStoredProcedures(databaseId, collectionId)
+	sps, status := h.dataStore.GetAllStoredProcedures(databaseId, collectionId)
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.Header("x-ms-item-count", fmt.Sprintf("%d", len(sps)))
 		c.IndentedJSON(http.StatusOK, gin.H{"_rid": "", "StoredProcedures": sps, "_count": len(sps)})
 		return
@@ -28,14 +28,14 @@ func (h *Handlers) GetStoredProcedure(c *gin.Context) {
 	collectionId := c.Param("collId")
 	spId := c.Param("spId")
 
-	sp, status := h.repository.GetStoredProcedure(databaseId, collectionId, spId)
+	sp, status := h.dataStore.GetStoredProcedure(databaseId, collectionId, spId)
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, sp)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -48,13 +48,13 @@ func (h *Handlers) DeleteStoredProcedure(c *gin.Context) {
 	collectionId := c.Param("collId")
 	spId := c.Param("spId")
 
-	status := h.repository.DeleteStoredProcedure(databaseId, collectionId, spId)
-	if status == repositorymodels.StatusOk {
+	status := h.dataStore.DeleteStoredProcedure(databaseId, collectionId, spId)
+	if status == datastore.StatusOk {
 		c.Status(http.StatusNoContent)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -67,25 +67,25 @@ func (h *Handlers) ReplaceStoredProcedure(c *gin.Context) {
 	collectionId := c.Param("collId")
 	spId := c.Param("spId")
 
-	var sp repositorymodels.StoredProcedure
+	var sp datastore.StoredProcedure
 	if err := c.BindJSON(&sp); err != nil {
 		c.IndentedJSON(http.StatusBadRequest, gin.H{"message": "Invalid body"})
 		return
 	}
 
-	status := h.repository.DeleteStoredProcedure(databaseId, collectionId, spId)
-	if status == repositorymodels.StatusNotFound {
+	status := h.dataStore.DeleteStoredProcedure(databaseId, collectionId, spId)
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
 
-	createdSP, status := h.repository.CreateStoredProcedure(databaseId, collectionId, sp)
-	if status == repositorymodels.Conflict {
+	createdSP, status := h.dataStore.CreateStoredProcedure(databaseId, collectionId, sp)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, createdSP)
 		return
 	}
@@ -97,19 +97,19 @@ func (h *Handlers) CreateStoredProcedure(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
 
-	var sp repositorymodels.StoredProcedure
+	var sp datastore.StoredProcedure
 	if err := c.BindJSON(&sp); err != nil {
 		c.IndentedJSON(http.StatusBadRequest, gin.H{"message": "Invalid body"})
 		return
 	}
 
-	createdSP, status := h.repository.CreateStoredProcedure(databaseId, collectionId, sp)
-	if status == repositorymodels.Conflict {
+	createdSP, status := h.dataStore.CreateStoredProcedure(databaseId, collectionId, sp)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdSP)
 		return
 	}

api/handlers/triggers.go

@@ -5,16 +5,16 @@ import (
 	"net/http"
 
 	"github.com/gin-gonic/gin"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 func (h *Handlers) GetAllTriggers(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
 
-	triggers, status := h.repository.GetAllTriggers(databaseId, collectionId)
+	triggers, status := h.dataStore.GetAllTriggers(databaseId, collectionId)
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.Header("x-ms-item-count", fmt.Sprintf("%d", len(triggers)))
 		c.IndentedJSON(http.StatusOK, gin.H{"_rid": "", "Triggers": triggers, "_count": len(triggers)})
 		return
@@ -28,14 +28,14 @@ func (h *Handlers) GetTrigger(c *gin.Context) {
 	collectionId := c.Param("collId")
 	triggerId := c.Param("triggerId")
 
-	trigger, status := h.repository.GetTrigger(databaseId, collectionId, triggerId)
+	trigger, status := h.dataStore.GetTrigger(databaseId, collectionId, triggerId)
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, trigger)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -48,13 +48,13 @@ func (h *Handlers) DeleteTrigger(c *gin.Context) {
 	collectionId := c.Param("collId")
 	triggerId := c.Param("triggerId")
 
-	status := h.repository.DeleteTrigger(databaseId, collectionId, triggerId)
-	if status == repositorymodels.StatusOk {
+	status := h.dataStore.DeleteTrigger(databaseId, collectionId, triggerId)
+	if status == datastore.StatusOk {
 		c.Status(http.StatusNoContent)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -67,25 +67,25 @@ func (h *Handlers) ReplaceTrigger(c *gin.Context) {
 	collectionId := c.Param("collId")
 	triggerId := c.Param("triggerId")
 
-	var trigger repositorymodels.Trigger
+	var trigger datastore.Trigger
 	if err := c.BindJSON(&trigger); err != nil {
 		c.IndentedJSON(http.StatusBadRequest, gin.H{"message": "Invalid body"})
 		return
 	}
 
-	status := h.repository.DeleteTrigger(databaseId, collectionId, triggerId)
-	if status == repositorymodels.StatusNotFound {
+	status := h.dataStore.DeleteTrigger(databaseId, collectionId, triggerId)
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
 
-	createdTrigger, status := h.repository.CreateTrigger(databaseId, collectionId, trigger)
-	if status == repositorymodels.Conflict {
+	createdTrigger, status := h.dataStore.CreateTrigger(databaseId, collectionId, trigger)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, createdTrigger)
 		return
 	}
@@ -97,19 +97,19 @@ func (h *Handlers) CreateTrigger(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
 
-	var trigger repositorymodels.Trigger
+	var trigger datastore.Trigger
 	if err := c.BindJSON(&trigger); err != nil {
 		c.IndentedJSON(http.StatusBadRequest, gin.H{"message": "Invalid body"})
 		return
 	}
 
-	createdTrigger, status := h.repository.CreateTrigger(databaseId, collectionId, trigger)
-	if status == repositorymodels.Conflict {
+	createdTrigger, status := h.dataStore.CreateTrigger(databaseId, collectionId, trigger)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdTrigger)
 		return
 	}

api/handlers/user_defined_functions.go

@@ -5,16 +5,16 @@ import (
 	"net/http"
 
 	"github.com/gin-gonic/gin"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 func (h *Handlers) GetAllUserDefinedFunctions(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
 
-	udfs, status := h.repository.GetAllUserDefinedFunctions(databaseId, collectionId)
+	udfs, status := h.dataStore.GetAllUserDefinedFunctions(databaseId, collectionId)
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.Header("x-ms-item-count", fmt.Sprintf("%d", len(udfs)))
 		c.IndentedJSON(http.StatusOK, gin.H{"_rid": "", "UserDefinedFunctions": udfs, "_count": len(udfs)})
 		return
@@ -28,14 +28,14 @@ func (h *Handlers) GetUserDefinedFunction(c *gin.Context) {
 	collectionId := c.Param("collId")
 	udfId := c.Param("udfId")
 
-	udf, status := h.repository.GetUserDefinedFunction(databaseId, collectionId, udfId)
+	udf, status := h.dataStore.GetUserDefinedFunction(databaseId, collectionId, udfId)
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, udf)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -48,13 +48,13 @@ func (h *Handlers) DeleteUserDefinedFunction(c *gin.Context) {
 	collectionId := c.Param("collId")
 	udfId := c.Param("udfId")
 
-	status := h.repository.DeleteUserDefinedFunction(databaseId, collectionId, udfId)
-	if status == repositorymodels.StatusOk {
+	status := h.dataStore.DeleteUserDefinedFunction(databaseId, collectionId, udfId)
+	if status == datastore.StatusOk {
 		c.Status(http.StatusNoContent)
 		return
 	}
 
-	if status == repositorymodels.StatusNotFound {
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
@@ -67,25 +67,25 @@ func (h *Handlers) ReplaceUserDefinedFunction(c *gin.Context) {
 	collectionId := c.Param("collId")
 	udfId := c.Param("udfId")
 
-	var udf repositorymodels.UserDefinedFunction
+	var udf datastore.UserDefinedFunction
 	if err := c.BindJSON(&udf); err != nil {
 		c.IndentedJSON(http.StatusBadRequest, gin.H{"message": "Invalid body"})
 		return
 	}
 
-	status := h.repository.DeleteUserDefinedFunction(databaseId, collectionId, udfId)
-	if status == repositorymodels.StatusNotFound {
+	status := h.dataStore.DeleteUserDefinedFunction(databaseId, collectionId, udfId)
+	if status == datastore.StatusNotFound {
 		c.IndentedJSON(http.StatusNotFound, gin.H{"message": "NotFound"})
 		return
 	}
 
-	createdUdf, status := h.repository.CreateUserDefinedFunction(databaseId, collectionId, udf)
-	if status == repositorymodels.Conflict {
+	createdUdf, status := h.dataStore.CreateUserDefinedFunction(databaseId, collectionId, udf)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusOK, createdUdf)
 		return
 	}
@@ -97,19 +97,19 @@ func (h *Handlers) CreateUserDefinedFunction(c *gin.Context) {
 	databaseId := c.Param("databaseId")
 	collectionId := c.Param("collId")
 
-	var udf repositorymodels.UserDefinedFunction
+	var udf datastore.UserDefinedFunction
 	if err := c.BindJSON(&udf); err != nil {
 		c.IndentedJSON(http.StatusBadRequest, gin.H{"message": "Invalid body"})
 		return
 	}
 
-	createdUdf, status := h.repository.CreateUserDefinedFunction(databaseId, collectionId, udf)
-	if status == repositorymodels.Conflict {
+	createdUdf, status := h.dataStore.CreateUserDefinedFunction(databaseId, collectionId, udf)
+	if status == datastore.Conflict {
 		c.IndentedJSON(http.StatusConflict, gin.H{"message": "Conflict"})
 		return
 	}
 
-	if status == repositorymodels.StatusOk {
+	if status == datastore.StatusOk {
 		c.IndentedJSON(http.StatusCreated, createdUdf)
 		return
 	}

api/router.go

@@ -10,15 +10,15 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/pikami/cosmium/api/handlers"
 	"github.com/pikami/cosmium/api/handlers/middleware"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/logger"
-	"github.com/pikami/cosmium/internal/repositories"
 	tlsprovider "github.com/pikami/cosmium/internal/tls_provider"
 )
 
 var ginMux sync.Mutex
 
-func (s *ApiServer) CreateRouter(repository *repositories.DataRepository) {
-	routeHandlers := handlers.NewHandlers(repository, s.config)
+func (s *ApiServer) CreateRouter(dataStore datastore.DataStore) {
+	routeHandlers := handlers.NewHandlers(dataStore, s.config)
 
 	ginMux.Lock()
 	gin.DefaultWriter = logger.InfoWriter()

api/tests/authentication_test.go

@@ -17,7 +17,7 @@ func Test_Authentication(t *testing.T) {
 	defer ts.Server.Close()
 
 	t.Run("Should get 200 when correct account key is used", func(t *testing.T) {
-		ts.Repository.DeleteDatabase(testDatabaseName)
+		ts.DataStore.DeleteDatabase(testDatabaseName)
 		client, err := azcosmos.NewClientFromConnectionString(
 			fmt.Sprintf("AccountEndpoint=%s;AccountKey=%s", ts.URL, config.DefaultAccountKey),
 			&azcosmos.ClientOptions{},
@@ -33,7 +33,7 @@ func Test_Authentication(t *testing.T) {
 	})
 
 	t.Run("Should get 401 when wrong account key is used", func(t *testing.T) {
-		ts.Repository.DeleteDatabase(testDatabaseName)
+		ts.DataStore.DeleteDatabase(testDatabaseName)
 		client, err := azcosmos.NewClientFromConnectionString(
 			fmt.Sprintf("AccountEndpoint=%s;AccountKey=%s", ts.URL, "AAAA"),
 			&azcosmos.ClientOptions{},
@@ -70,7 +70,7 @@ func Test_Authentication_Disabled(t *testing.T) {
 	defer ts.Server.Close()
 
 	t.Run("Should get 200 when wrong account key is used, but authentication is dissabled", func(t *testing.T) {
-		ts.Repository.DeleteDatabase(testDatabaseName)
+		ts.DataStore.DeleteDatabase(testDatabaseName)
 		client, err := azcosmos.NewClientFromConnectionString(
 			fmt.Sprintf("AccountEndpoint=%s;AccountKey=%s", ts.URL, "AAAA"),
 			&azcosmos.ClientOptions{},

api/tests/collections_test.go

@@ -10,7 +10,7 @@ import (
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore"
 	"github.com/Azure/azure-sdk-for-go/sdk/data/azcosmos"
 	"github.com/pikami/cosmium/api/config"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -24,7 +24,7 @@ func Test_Collections(t *testing.T) {
 	)
 	assert.Nil(t, err)
 
-	ts.Repository.CreateDatabase(repositorymodels.Database{ID: testDatabaseName})
+	ts.DataStore.CreateDatabase(datastore.Database{ID: testDatabaseName})
 	databaseClient, err := client.NewDatabase(testDatabaseName)
 	assert.Nil(t, err)
 
@@ -39,7 +39,7 @@ func Test_Collections(t *testing.T) {
 		})
 
 		t.Run("Should return conflict when collection exists", func(t *testing.T) {
-			ts.Repository.CreateCollection(testDatabaseName, repositorymodels.Collection{
+			ts.DataStore.CreateCollection(testDatabaseName, datastore.Collection{
 				ID: testCollectionName,
 			})
 
@@ -59,7 +59,7 @@ func Test_Collections(t *testing.T) {
 
 	t.Run("Collection Read", func(t *testing.T) {
 		t.Run("Should read collection", func(t *testing.T) {
-			ts.Repository.CreateCollection(testDatabaseName, repositorymodels.Collection{
+			ts.DataStore.CreateCollection(testDatabaseName, datastore.Collection{
 				ID: testCollectionName,
 			})
 
@@ -73,7 +73,7 @@ func Test_Collections(t *testing.T) {
 		})
 
 		t.Run("Should return not found when collection does not exist", func(t *testing.T) {
-			ts.Repository.DeleteCollection(testDatabaseName, testCollectionName)
+			ts.DataStore.DeleteCollection(testDatabaseName, testCollectionName)
 
 			collectionResponse, err := databaseClient.NewContainer(testCollectionName)
 			assert.Nil(t, err)
@@ -92,7 +92,7 @@ func Test_Collections(t *testing.T) {
 
 	t.Run("Collection Delete", func(t *testing.T) {
 		t.Run("Should delete collection", func(t *testing.T) {
-			ts.Repository.CreateCollection(testDatabaseName, repositorymodels.Collection{
+			ts.DataStore.CreateCollection(testDatabaseName, datastore.Collection{
 				ID: testCollectionName,
 			})
 
@@ -105,7 +105,7 @@ func Test_Collections(t *testing.T) {
 		})
 
 		t.Run("Should return not found when collection does not exist", func(t *testing.T) {
-			ts.Repository.DeleteCollection(testDatabaseName, testCollectionName)
+			ts.DataStore.DeleteCollection(testDatabaseName, testCollectionName)
 
 			collectionResponse, err := databaseClient.NewContainer(testCollectionName)
 			assert.Nil(t, err)

api/tests/config_test.go

@@ -5,29 +5,30 @@ import (
 
 	"github.com/pikami/cosmium/api"
 	"github.com/pikami/cosmium/api/config"
+	"github.com/pikami/cosmium/internal/datastore"
+	mapdatastore "github.com/pikami/cosmium/internal/datastore/map_datastore"
 	"github.com/pikami/cosmium/internal/logger"
-	"github.com/pikami/cosmium/internal/repositories"
 )
 
 type TestServer struct {
-	Server     *httptest.Server
-	Repository *repositories.DataRepository
-	URL        string
+	Server    *httptest.Server
+	DataStore datastore.DataStore
+	URL       string
 }
 
 func runTestServerCustomConfig(config *config.ServerConfig) *TestServer {
-	repository := repositories.NewDataRepository(repositories.RepositoryOptions{})
+	dataStore := mapdatastore.NewMapDataStore(mapdatastore.MapDataStoreOptions{})
 
-	api := api.NewApiServer(repository, config)
+	api := api.NewApiServer(dataStore, config)
 
 	server := httptest.NewServer(api.GetRouter())
 
 	config.DatabaseEndpoint = server.URL
 
 	return &TestServer{
-		Server:     server,
-		Repository: repository,
-		URL:        server.URL,
+		Server:    server,
+		DataStore: dataStore,
+		URL:       server.URL,
 	}
 }
 

api/tests/databases_test.go

@@ -10,7 +10,7 @@ import (
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore"
 	"github.com/Azure/azure-sdk-for-go/sdk/data/azcosmos"
 	"github.com/pikami/cosmium/api/config"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -26,7 +26,7 @@ func Test_Databases(t *testing.T) {
 
 	t.Run("Database Create", func(t *testing.T) {
 		t.Run("Should create database", func(t *testing.T) {
-			ts.Repository.DeleteDatabase(testDatabaseName)
+			ts.DataStore.DeleteDatabase(testDatabaseName)
 
 			createResponse, err := client.CreateDatabase(context.TODO(), azcosmos.DatabaseProperties{
 				ID: testDatabaseName,
@@ -37,7 +37,7 @@ func Test_Databases(t *testing.T) {
 		})
 
 		t.Run("Should return conflict when database exists", func(t *testing.T) {
-			ts.Repository.CreateDatabase(repositorymodels.Database{
+			ts.DataStore.CreateDatabase(datastore.Database{
 				ID: testDatabaseName,
 			})
 
@@ -57,7 +57,7 @@ func Test_Databases(t *testing.T) {
 
 	t.Run("Database Read", func(t *testing.T) {
 		t.Run("Should read database", func(t *testing.T) {
-			ts.Repository.CreateDatabase(repositorymodels.Database{
+			ts.DataStore.CreateDatabase(datastore.Database{
 				ID: testDatabaseName,
 			})
 
@@ -71,7 +71,7 @@ func Test_Databases(t *testing.T) {
 		})
 
 		t.Run("Should return not found when database does not exist", func(t *testing.T) {
-			ts.Repository.DeleteDatabase(testDatabaseName)
+			ts.DataStore.DeleteDatabase(testDatabaseName)
 
 			databaseResponse, err := client.NewDatabase(testDatabaseName)
 			assert.Nil(t, err)
@@ -90,7 +90,7 @@ func Test_Databases(t *testing.T) {
 
 	t.Run("Database Delete", func(t *testing.T) {
 		t.Run("Should delete database", func(t *testing.T) {
-			ts.Repository.CreateDatabase(repositorymodels.Database{
+			ts.DataStore.CreateDatabase(datastore.Database{
 				ID: testDatabaseName,
 			})
 
@@ -103,7 +103,7 @@ func Test_Databases(t *testing.T) {
 		})
 
 		t.Run("Should return not found when database does not exist", func(t *testing.T) {
-			ts.Repository.DeleteDatabase(testDatabaseName)
+			ts.DataStore.DeleteDatabase(testDatabaseName)
 
 			databaseResponse, err := client.NewDatabase(testDatabaseName)
 			assert.Nil(t, err)

api/tests/documents_test.go

@@ -14,7 +14,7 @@ import (
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore"
 	"github.com/Azure/azure-sdk-for-go/sdk/data/azcosmos"
 	"github.com/pikami/cosmium/api/config"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -56,8 +56,8 @@ func testCosmosQuery(t *testing.T,
 func documents_InitializeDb(t *testing.T) (*TestServer, *azcosmos.ContainerClient) {
 	ts := runTestServer()
 
-	ts.Repository.CreateDatabase(repositorymodels.Database{ID: testDatabaseName})
-	ts.Repository.CreateCollection(testDatabaseName, repositorymodels.Collection{
+	ts.DataStore.CreateDatabase(datastore.Database{ID: testDatabaseName})
+	ts.DataStore.CreateCollection(testDatabaseName, datastore.Collection{
 		ID: testCollectionName,
 		PartitionKey: struct {
 			Paths   []string "json:\"paths\""
@@ -67,8 +67,8 @@ func documents_InitializeDb(t *testing.T) (*TestServer, *azcosmos.ContainerClien
 			Paths: []string{"/pk"},
 		},
 	})
-	ts.Repository.CreateDocument(testDatabaseName, testCollectionName, map[string]interface{}{"id": "12345", "pk": "123", "isCool": false, "arr": []int{1, 2, 3}})
-	ts.Repository.CreateDocument(testDatabaseName, testCollectionName, map[string]interface{}{"id": "67890", "pk": "456", "isCool": true, "arr": []int{6, 7, 8}})
+	ts.DataStore.CreateDocument(testDatabaseName, testCollectionName, map[string]interface{}{"id": "12345", "pk": "123", "isCool": false, "arr": []int{1, 2, 3}})
+	ts.DataStore.CreateDocument(testDatabaseName, testCollectionName, map[string]interface{}{"id": "67890", "pk": "456", "isCool": true, "arr": []int{6, 7, 8}})
 
 	client, err := azcosmos.NewClientFromConnectionString(
 		fmt.Sprintf("AccountEndpoint=%s;AccountKey=%s", ts.URL, config.DefaultAccountKey),
@@ -408,7 +408,7 @@ func Test_Documents_TransactionalBatch(t *testing.T) {
 		json.Unmarshal(operationResponse.ResourceBody, &itemResponseBody)
 		assert.Equal(t, newItem["id"], itemResponseBody["id"])
 
-		createdDoc, _ := ts.Repository.GetDocument(testDatabaseName, testCollectionName, newItem["id"].(string))
+		createdDoc, _ := ts.DataStore.GetDocument(testDatabaseName, testCollectionName, newItem["id"].(string))
 		assert.Equal(t, newItem["id"], createdDoc["id"])
 	})
 
@@ -426,8 +426,8 @@ func Test_Documents_TransactionalBatch(t *testing.T) {
 		assert.NotNil(t, operationResponse)
 		assert.Equal(t, int32(http.StatusNoContent), operationResponse.StatusCode)
 
-		_, status := ts.Repository.GetDocument(testDatabaseName, testCollectionName, "12345")
-		assert.Equal(t, repositorymodels.StatusNotFound, int(status))
+		_, status := ts.DataStore.GetDocument(testDatabaseName, testCollectionName, "12345")
+		assert.Equal(t, datastore.StatusNotFound, int(status))
 	})
 
 	t.Run("Should execute REPLACE transactional batch", func(t *testing.T) {
@@ -457,7 +457,7 @@ func Test_Documents_TransactionalBatch(t *testing.T) {
 		assert.Equal(t, newItem["id"], itemResponseBody["id"])
 		assert.Equal(t, newItem["pk"], itemResponseBody["pk"])
 
-		updatedDoc, _ := ts.Repository.GetDocument(testDatabaseName, testCollectionName, newItem["id"].(string))
+		updatedDoc, _ := ts.DataStore.GetDocument(testDatabaseName, testCollectionName, newItem["id"].(string))
 		assert.Equal(t, newItem["id"], updatedDoc["id"])
 		assert.Equal(t, newItem["pk"], updatedDoc["pk"])
 	})
@@ -489,7 +489,7 @@ func Test_Documents_TransactionalBatch(t *testing.T) {
 		assert.Equal(t, newItem["id"], itemResponseBody["id"])
 		assert.Equal(t, newItem["pk"], itemResponseBody["pk"])
 
-		updatedDoc, _ := ts.Repository.GetDocument(testDatabaseName, testCollectionName, newItem["id"].(string))
+		updatedDoc, _ := ts.DataStore.GetDocument(testDatabaseName, testCollectionName, newItem["id"].(string))
 		assert.Equal(t, newItem["id"], updatedDoc["id"])
 		assert.Equal(t, newItem["pk"], updatedDoc["pk"])
 	})

cmd/server/server.go

@@ -7,27 +7,28 @@ import (
 
 	"github.com/pikami/cosmium/api"
 	"github.com/pikami/cosmium/api/config"
-	"github.com/pikami/cosmium/internal/repositories"
+	"github.com/pikami/cosmium/internal/datastore"
+	mapdatastore "github.com/pikami/cosmium/internal/datastore/map_datastore"
 )
 
 func main() {
 	configuration := config.ParseFlags()
 
-	repository := repositories.NewDataRepository(repositories.RepositoryOptions{
+	var dataStore datastore.DataStore = mapdatastore.NewMapDataStore(mapdatastore.MapDataStoreOptions{
 		InitialDataFilePath: configuration.InitialDataFilePath,
 		PersistDataFilePath: configuration.PersistDataFilePath,
 	})
 
-	server := api.NewApiServer(repository, &configuration)
+	server := api.NewApiServer(dataStore, &configuration)
 	err := server.Start()
 	if err != nil {
 		panic(err)
 	}
 
-	waitForExit(server, repository, configuration)
+	waitForExit(server, dataStore, configuration)
 }
 
-func waitForExit(server *api.ApiServer, repository *repositories.DataRepository, config config.ServerConfig) {
+func waitForExit(server *api.ApiServer, dataStore datastore.DataStore, config config.ServerConfig) {
 	sigs := make(chan os.Signal, 1)
 	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
 
@@ -37,7 +38,5 @@ func waitForExit(server *api.ApiServer, repository *repositories.DataRepository,
 	// Stop the server
 	server.Stop()
 
-	if config.PersistDataFilePath != "" {
-		repository.SaveStateFS(config.PersistDataFilePath)
-	}
+	dataStore.Close()
 }

internal/converters/document_to_rowtype.go

@@ -0,0 +1,20 @@
+package converters
+
+import (
+	"github.com/pikami/cosmium/internal/datastore"
+	memoryexecutor "github.com/pikami/cosmium/query_executors/memory_executor"
+)
+
+type DocumentToRowTypeIterator struct {
+	documents datastore.DocumentIterator
+}
+
+func NewDocumentToRowTypeIterator(documents datastore.DocumentIterator) *DocumentToRowTypeIterator {
+	return &DocumentToRowTypeIterator{
+		documents: documents,
+	}
+}
+
+func (di *DocumentToRowTypeIterator) Next() (memoryexecutor.RowType, datastore.DataStoreStatus) {
+	return di.documents.Next()
+}

internal/datastore/datastore.go

@@ -0,0 +1,43 @@
+package datastore
+
+type DataStore interface {
+	GetAllDatabases() ([]Database, DataStoreStatus)
+	GetDatabase(databaseId string) (Database, DataStoreStatus)
+	DeleteDatabase(databaseId string) DataStoreStatus
+	CreateDatabase(newDatabase Database) (Database, DataStoreStatus)
+
+	GetAllCollections(databaseId string) ([]Collection, DataStoreStatus)
+	GetCollection(databaseId string, collectionId string) (Collection, DataStoreStatus)
+	DeleteCollection(databaseId string, collectionId string) DataStoreStatus
+	CreateCollection(databaseId string, newCollection Collection) (Collection, DataStoreStatus)
+
+	GetAllDocuments(databaseId string, collectionId string) ([]Document, DataStoreStatus)
+	GetDocumentIterator(databaseId string, collectionId string) (DocumentIterator, DataStoreStatus)
+	GetDocument(databaseId string, collectionId string, documentId string) (Document, DataStoreStatus)
+	DeleteDocument(databaseId string, collectionId string, documentId string) DataStoreStatus
+	CreateDocument(databaseId string, collectionId string, document map[string]interface{}) (Document, DataStoreStatus)
+
+	GetAllTriggers(databaseId string, collectionId string) ([]Trigger, DataStoreStatus)
+	GetTrigger(databaseId string, collectionId string, triggerId string) (Trigger, DataStoreStatus)
+	DeleteTrigger(databaseId string, collectionId string, triggerId string) DataStoreStatus
+	CreateTrigger(databaseId string, collectionId string, trigger Trigger) (Trigger, DataStoreStatus)
+
+	GetAllStoredProcedures(databaseId string, collectionId string) ([]StoredProcedure, DataStoreStatus)
+	GetStoredProcedure(databaseId string, collectionId string, storedProcedureId string) (StoredProcedure, DataStoreStatus)
+	DeleteStoredProcedure(databaseId string, collectionId string, storedProcedureId string) DataStoreStatus
+	CreateStoredProcedure(databaseId string, collectionId string, storedProcedure StoredProcedure) (StoredProcedure, DataStoreStatus)
+
+	GetAllUserDefinedFunctions(databaseId string, collectionId string) ([]UserDefinedFunction, DataStoreStatus)
+	GetUserDefinedFunction(databaseId string, collectionId string, udfId string) (UserDefinedFunction, DataStoreStatus)
+	DeleteUserDefinedFunction(databaseId string, collectionId string, udfId string) DataStoreStatus
+	CreateUserDefinedFunction(databaseId string, collectionId string, udf UserDefinedFunction) (UserDefinedFunction, DataStoreStatus)
+
+	GetPartitionKeyRanges(databaseId string, collectionId string) ([]PartitionKeyRange, DataStoreStatus)
+
+	Close()
+	DumpToJson() (string, error)
+}
+
+type DocumentIterator interface {
+	Next() (Document, DataStoreStatus)
+}

internal/datastore/map_datastore/array_document_iterator.go

@@ -0,0 +1,17 @@
+package mapdatastore
+
+import "github.com/pikami/cosmium/internal/datastore"
+
+type ArrayDocumentIterator struct {
+	documents []datastore.Document
+	index     int
+}
+
+func (i *ArrayDocumentIterator) Next() (datastore.Document, datastore.DataStoreStatus) {
+	i.index++
+	if i.index >= len(i.documents) {
+		return datastore.Document{}, datastore.StatusNotFound
+	}
+
+	return i.documents[i.index], datastore.StatusOk
+}

internal/datastore/map_datastore/collections.go

@@ -1,52 +1,52 @@
-package repositories
+package mapdatastore
 
 import (
 	"fmt"
 	"time"
 
 	"github.com/google/uuid"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/resourceid"
 	structhidrators "github.com/pikami/cosmium/internal/struct_hidrators"
 	"golang.org/x/exp/maps"
 )
 
-func (r *DataRepository) GetAllCollections(databaseId string) ([]repositorymodels.Collection, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) GetAllCollections(databaseId string) ([]datastore.Collection, datastore.DataStoreStatus) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
 	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return make([]repositorymodels.Collection, 0), repositorymodels.StatusNotFound
+		return make([]datastore.Collection, 0), datastore.StatusNotFound
 	}
 
-	return maps.Values(r.storeState.Collections[databaseId]), repositorymodels.StatusOk
+	return maps.Values(r.storeState.Collections[databaseId]), datastore.StatusOk
 }
 
-func (r *DataRepository) GetCollection(databaseId string, collectionId string) (repositorymodels.Collection, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) GetCollection(databaseId string, collectionId string) (datastore.Collection, datastore.DataStoreStatus) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
 	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.Collection{}, repositorymodels.StatusNotFound
+		return datastore.Collection{}, datastore.StatusNotFound
 	}
 
 	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.Collection{}, repositorymodels.StatusNotFound
+		return datastore.Collection{}, datastore.StatusNotFound
 	}
 
-	return r.storeState.Collections[databaseId][collectionId], repositorymodels.StatusOk
+	return r.storeState.Collections[databaseId][collectionId], datastore.StatusOk
 }
 
-func (r *DataRepository) DeleteCollection(databaseId string, collectionId string) repositorymodels.RepositoryStatus {
+func (r *MapDataStore) DeleteCollection(databaseId string, collectionId string) datastore.DataStoreStatus {
 	r.storeState.Lock()
 	defer r.storeState.Unlock()
 
 	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.StatusNotFound
+		return datastore.StatusNotFound
 	}
 
 	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.StatusNotFound
+		return datastore.StatusNotFound
 	}
 
 	delete(r.storeState.Collections[databaseId], collectionId)
@@ -55,24 +55,24 @@ func (r *DataRepository) DeleteCollection(databaseId string, collectionId string
 	delete(r.storeState.StoredProcedures[databaseId], collectionId)
 	delete(r.storeState.UserDefinedFunctions[databaseId], collectionId)
 
-	return repositorymodels.StatusOk
+	return datastore.StatusOk
 }
 
-func (r *DataRepository) CreateCollection(databaseId string, newCollection repositorymodels.Collection) (repositorymodels.Collection, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) CreateCollection(databaseId string, newCollection datastore.Collection) (datastore.Collection, datastore.DataStoreStatus) {
 	r.storeState.Lock()
 	defer r.storeState.Unlock()
 
 	var ok bool
-	var database repositorymodels.Database
+	var database datastore.Database
 	if database, ok = r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.Collection{}, repositorymodels.StatusNotFound
+		return datastore.Collection{}, datastore.StatusNotFound
 	}
 
 	if _, ok = r.storeState.Collections[databaseId][newCollection.ID]; ok {
-		return repositorymodels.Collection{}, repositorymodels.Conflict
+		return datastore.Collection{}, datastore.Conflict
 	}
 
-	newCollection = structhidrators.Hidrate(newCollection).(repositorymodels.Collection)
+	newCollection = structhidrators.Hidrate(newCollection).(datastore.Collection)
 
 	newCollection.TimeStamp = time.Now().Unix()
 	newCollection.ResourceID = resourceid.NewCombined(database.ResourceID, resourceid.New(resourceid.ResourceTypeCollection))
@@ -80,10 +80,10 @@ func (r *DataRepository) CreateCollection(databaseId string, newCollection repos
 	newCollection.Self = fmt.Sprintf("dbs/%s/colls/%s/", database.ResourceID, newCollection.ResourceID)
 
 	r.storeState.Collections[databaseId][newCollection.ID] = newCollection
-	r.storeState.Documents[databaseId][newCollection.ID] = make(map[string]repositorymodels.Document)
-	r.storeState.Triggers[databaseId][newCollection.ID] = make(map[string]repositorymodels.Trigger)
-	r.storeState.StoredProcedures[databaseId][newCollection.ID] = make(map[string]repositorymodels.StoredProcedure)
-	r.storeState.UserDefinedFunctions[databaseId][newCollection.ID] = make(map[string]repositorymodels.UserDefinedFunction)
+	r.storeState.Documents[databaseId][newCollection.ID] = make(map[string]datastore.Document)
+	r.storeState.Triggers[databaseId][newCollection.ID] = make(map[string]datastore.Trigger)
+	r.storeState.StoredProcedures[databaseId][newCollection.ID] = make(map[string]datastore.StoredProcedure)
+	r.storeState.UserDefinedFunctions[databaseId][newCollection.ID] = make(map[string]datastore.UserDefinedFunction)
 
-	return newCollection, repositorymodels.StatusOk
+	return newCollection, datastore.StatusOk
 }

internal/datastore/map_datastore/databases.go

@@ -1,39 +1,39 @@
-package repositories
+package mapdatastore
 
 import (
 	"fmt"
 	"time"
 
 	"github.com/google/uuid"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/resourceid"
 	"golang.org/x/exp/maps"
 )
 
-func (r *DataRepository) GetAllDatabases() ([]repositorymodels.Database, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) GetAllDatabases() ([]datastore.Database, datastore.DataStoreStatus) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
-	return maps.Values(r.storeState.Databases), repositorymodels.StatusOk
+	return maps.Values(r.storeState.Databases), datastore.StatusOk
 }
 
-func (r *DataRepository) GetDatabase(id string) (repositorymodels.Database, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) GetDatabase(id string) (datastore.Database, datastore.DataStoreStatus) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
 	if database, ok := r.storeState.Databases[id]; ok {
-		return database, repositorymodels.StatusOk
+		return database, datastore.StatusOk
 	}
 
-	return repositorymodels.Database{}, repositorymodels.StatusNotFound
+	return datastore.Database{}, datastore.StatusNotFound
 }
 
-func (r *DataRepository) DeleteDatabase(id string) repositorymodels.RepositoryStatus {
+func (r *MapDataStore) DeleteDatabase(id string) datastore.DataStoreStatus {
 	r.storeState.Lock()
 	defer r.storeState.Unlock()
 
 	if _, ok := r.storeState.Databases[id]; !ok {
-		return repositorymodels.StatusNotFound
+		return datastore.StatusNotFound
 	}
 
 	delete(r.storeState.Databases, id)
@@ -43,15 +43,15 @@ func (r *DataRepository) DeleteDatabase(id string) repositorymodels.RepositorySt
 	delete(r.storeState.StoredProcedures, id)
 	delete(r.storeState.UserDefinedFunctions, id)
 
-	return repositorymodels.StatusOk
+	return datastore.StatusOk
 }
 
-func (r *DataRepository) CreateDatabase(newDatabase repositorymodels.Database) (repositorymodels.Database, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) CreateDatabase(newDatabase datastore.Database) (datastore.Database, datastore.DataStoreStatus) {
 	r.storeState.Lock()
 	defer r.storeState.Unlock()
 
 	if _, ok := r.storeState.Databases[newDatabase.ID]; ok {
-		return repositorymodels.Database{}, repositorymodels.Conflict
+		return datastore.Database{}, datastore.Conflict
 	}
 
 	newDatabase.TimeStamp = time.Now().Unix()
@@ -60,11 +60,11 @@ func (r *DataRepository) CreateDatabase(newDatabase repositorymodels.Database) (
 	newDatabase.Self = fmt.Sprintf("dbs/%s/", newDatabase.ResourceID)
 
 	r.storeState.Databases[newDatabase.ID] = newDatabase
-	r.storeState.Collections[newDatabase.ID] = make(map[string]repositorymodels.Collection)
-	r.storeState.Documents[newDatabase.ID] = make(map[string]map[string]repositorymodels.Document)
-	r.storeState.Triggers[newDatabase.ID] = make(map[string]map[string]repositorymodels.Trigger)
-	r.storeState.StoredProcedures[newDatabase.ID] = make(map[string]map[string]repositorymodels.StoredProcedure)
-	r.storeState.UserDefinedFunctions[newDatabase.ID] = make(map[string]map[string]repositorymodels.UserDefinedFunction)
+	r.storeState.Collections[newDatabase.ID] = make(map[string]datastore.Collection)
+	r.storeState.Documents[newDatabase.ID] = make(map[string]map[string]datastore.Document)
+	r.storeState.Triggers[newDatabase.ID] = make(map[string]map[string]datastore.Trigger)
+	r.storeState.StoredProcedures[newDatabase.ID] = make(map[string]map[string]datastore.StoredProcedure)
+	r.storeState.UserDefinedFunctions[newDatabase.ID] = make(map[string]map[string]datastore.UserDefinedFunction)
 
-	return newDatabase, repositorymodels.StatusOk
+	return newDatabase, datastore.StatusOk
 }

internal/datastore/map_datastore/documents.go

@@ -0,0 +1,113 @@
+package mapdatastore
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/internal/resourceid"
+	"golang.org/x/exp/maps"
+)
+
+func (r *MapDataStore) GetAllDocuments(databaseId string, collectionId string) ([]datastore.Document, datastore.DataStoreStatus) {
+	r.storeState.RLock()
+	defer r.storeState.RUnlock()
+
+	if _, ok := r.storeState.Databases[databaseId]; !ok {
+		return make([]datastore.Document, 0), datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
+		return make([]datastore.Document, 0), datastore.StatusNotFound
+	}
+
+	return maps.Values(r.storeState.Documents[databaseId][collectionId]), datastore.StatusOk
+}
+
+func (r *MapDataStore) GetDocument(databaseId string, collectionId string, documentId string) (datastore.Document, datastore.DataStoreStatus) {
+	r.storeState.RLock()
+	defer r.storeState.RUnlock()
+
+	if _, ok := r.storeState.Databases[databaseId]; !ok {
+		return datastore.Document{}, datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.Document{}, datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Documents[databaseId][collectionId][documentId]; !ok {
+		return datastore.Document{}, datastore.StatusNotFound
+	}
+
+	return r.storeState.Documents[databaseId][collectionId][documentId], datastore.StatusOk
+}
+
+func (r *MapDataStore) DeleteDocument(databaseId string, collectionId string, documentId string) datastore.DataStoreStatus {
+	r.storeState.Lock()
+	defer r.storeState.Unlock()
+
+	if _, ok := r.storeState.Databases[databaseId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Documents[databaseId][collectionId][documentId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	delete(r.storeState.Documents[databaseId][collectionId], documentId)
+
+	return datastore.StatusOk
+}
+
+func (r *MapDataStore) CreateDocument(databaseId string, collectionId string, document map[string]interface{}) (datastore.Document, datastore.DataStoreStatus) {
+	r.storeState.Lock()
+	defer r.storeState.Unlock()
+
+	var ok bool
+	var documentId string
+	var database datastore.Database
+	var collection datastore.Collection
+	if documentId, ok = document["id"].(string); !ok || documentId == "" {
+		documentId = fmt.Sprint(uuid.New())
+		document["id"] = documentId
+	}
+
+	if database, ok = r.storeState.Databases[databaseId]; !ok {
+		return datastore.Document{}, datastore.StatusNotFound
+	}
+
+	if collection, ok = r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.Document{}, datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Documents[databaseId][collectionId][documentId]; ok {
+		return datastore.Document{}, datastore.Conflict
+	}
+
+	document["_ts"] = time.Now().Unix()
+	document["_rid"] = resourceid.NewCombined(collection.ResourceID, resourceid.New(resourceid.ResourceTypeDocument))
+	document["_etag"] = fmt.Sprintf("\"%s\"", uuid.New())
+	document["_self"] = fmt.Sprintf("dbs/%s/colls/%s/docs/%s/", database.ResourceID, collection.ResourceID, document["_rid"])
+
+	r.storeState.Documents[databaseId][collectionId][documentId] = document
+
+	return document, datastore.StatusOk
+}
+
+func (r *MapDataStore) GetDocumentIterator(databaseId string, collectionId string) (datastore.DocumentIterator, datastore.DataStoreStatus) {
+	documents, status := r.GetAllDocuments(databaseId, collectionId)
+	if status != datastore.StatusOk {
+		return nil, status
+	}
+
+	return &ArrayDocumentIterator{
+		documents: documents,
+		index:     -1,
+	}, datastore.StatusOk
+}

internal/datastore/map_datastore/map_datastore.go

@@ -0,0 +1,34 @@
+package mapdatastore
+
+import "github.com/pikami/cosmium/internal/datastore"
+
+type MapDataStore struct {
+	storeState State
+
+	initialDataFilePath string
+	persistDataFilePath string
+}
+
+type MapDataStoreOptions struct {
+	InitialDataFilePath string
+	PersistDataFilePath string
+}
+
+func NewMapDataStore(options MapDataStoreOptions) *MapDataStore {
+	dataStore := &MapDataStore{
+		storeState: State{
+			Databases:            make(map[string]datastore.Database),
+			Collections:          make(map[string]map[string]datastore.Collection),
+			Documents:            make(map[string]map[string]map[string]datastore.Document),
+			Triggers:             make(map[string]map[string]map[string]datastore.Trigger),
+			StoredProcedures:     make(map[string]map[string]map[string]datastore.StoredProcedure),
+			UserDefinedFunctions: make(map[string]map[string]map[string]datastore.UserDefinedFunction),
+		},
+		initialDataFilePath: options.InitialDataFilePath,
+		persistDataFilePath: options.PersistDataFilePath,
+	}
+
+	dataStore.InitializeDataStore()
+
+	return dataStore
+}

internal/datastore/map_datastore/partition_key_ranges.go

@@ -1,15 +1,15 @@
-package repositories
+package mapdatastore
 
 import (
 	"fmt"
 
 	"github.com/google/uuid"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/resourceid"
 )
 
 // I have no idea what this is tbh
-func (r *DataRepository) GetPartitionKeyRanges(databaseId string, collectionId string) ([]repositorymodels.PartitionKeyRange, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) GetPartitionKeyRanges(databaseId string, collectionId string) ([]datastore.PartitionKeyRange, datastore.DataStoreStatus) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
@@ -30,7 +30,7 @@ func (r *DataRepository) GetPartitionKeyRanges(databaseId string, collectionId s
 	pkrSelf := fmt.Sprintf("dbs/%s/colls/%s/pkranges/%s/", databaseRid, collectionRid, pkrResourceId)
 	etag := fmt.Sprintf("\"%s\"", uuid.New())
 
-	return []repositorymodels.PartitionKeyRange{
+	return []datastore.PartitionKeyRange{
 		{
 			ResourceID:         pkrResourceId,
 			ID:                 "0",
@@ -45,5 +45,5 @@ func (r *DataRepository) GetPartitionKeyRanges(databaseId string, collectionId s
 			TimeStamp:          timestamp,
 			Lsn:                17,
 		},
-	}, repositorymodels.StatusOk
+	}, datastore.StatusOk
 }

internal/datastore/map_datastore/state.go

@@ -1,16 +1,39 @@
-package repositories
+package mapdatastore
 
 import (
 	"encoding/json"
 	"log"
 	"os"
 	"reflect"
+	"sync"
 
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/logger"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
 )
 
-func (r *DataRepository) InitializeRepository() {
+type State struct {
+	sync.RWMutex
+
+	// Map databaseId -> Database
+	Databases map[string]datastore.Database `json:"databases"`
+
+	// Map databaseId -> collectionId -> Collection
+	Collections map[string]map[string]datastore.Collection `json:"collections"`
+
+	// Map databaseId -> collectionId -> documentId -> Documents
+	Documents map[string]map[string]map[string]datastore.Document `json:"documents"`
+
+	// Map databaseId -> collectionId -> triggerId -> Trigger
+	Triggers map[string]map[string]map[string]datastore.Trigger `json:"triggers"`
+
+	// Map databaseId -> collectionId -> spId -> StoredProcedure
+	StoredProcedures map[string]map[string]map[string]datastore.StoredProcedure `json:"sprocs"`
+
+	// Map databaseId -> collectionId -> udfId -> UserDefinedFunction
+	UserDefinedFunctions map[string]map[string]map[string]datastore.UserDefinedFunction `json:"udfs"`
+}
+
+func (r *MapDataStore) InitializeDataStore() {
 	if r.initialDataFilePath != "" {
 		r.LoadStateFS(r.initialDataFilePath)
 		return
@@ -32,7 +55,7 @@ func (r *DataRepository) InitializeRepository() {
 	}
 }
 
-func (r *DataRepository) LoadStateFS(filePath string) {
+func (r *MapDataStore) LoadStateFS(filePath string) {
 	data, err := os.ReadFile(filePath)
 	if err != nil {
 		log.Fatalf("Error reading state JSON file: %v", err)
@@ -45,11 +68,11 @@ func (r *DataRepository) LoadStateFS(filePath string) {
 	}
 }
 
-func (r *DataRepository) LoadStateJSON(jsonData string) error {
+func (r *MapDataStore) LoadStateJSON(jsonData string) error {
 	r.storeState.Lock()
 	defer r.storeState.Unlock()
 
-	var state repositorymodels.State
+	var state State
 	if err := json.Unmarshal([]byte(jsonData), &state); err != nil {
 		return err
 	}
@@ -71,7 +94,7 @@ func (r *DataRepository) LoadStateJSON(jsonData string) error {
 	return nil
 }
 
-func (r *DataRepository) SaveStateFS(filePath string) {
+func (r *MapDataStore) SaveStateFS(filePath string) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
@@ -92,7 +115,7 @@ func (r *DataRepository) SaveStateFS(filePath string) {
 	logger.Infof("User defined functions: %d\n", getLength(r.storeState.UserDefinedFunctions))
 }
 
-func (r *DataRepository) GetState() (string, error) {
+func (r *MapDataStore) DumpToJson() (string, error) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
@@ -103,16 +126,23 @@ func (r *DataRepository) GetState() (string, error) {
 	}
 
 	return string(data), nil
+
+}
+
+func (r *MapDataStore) Close() {
+	if r.persistDataFilePath != "" {
+		r.SaveStateFS(r.persistDataFilePath)
+	}
 }
 
 func getLength(v interface{}) int {
 	switch v.(type) {
-	case repositorymodels.Database,
-		repositorymodels.Collection,
-		repositorymodels.Document,
-		repositorymodels.Trigger,
-		repositorymodels.StoredProcedure,
-		repositorymodels.UserDefinedFunction:
+	case datastore.Database,
+		datastore.Collection,
+		datastore.Document,
+		datastore.Trigger,
+		datastore.StoredProcedure,
+		datastore.UserDefinedFunction:
 		return 1
 	}
 
@@ -133,55 +163,55 @@ func getLength(v interface{}) int {
 	return count
 }
 
-func (r *DataRepository) ensureStoreStateNoNullReferences() {
+func (r *MapDataStore) ensureStoreStateNoNullReferences() {
 	if r.storeState.Databases == nil {
-		r.storeState.Databases = make(map[string]repositorymodels.Database)
+		r.storeState.Databases = make(map[string]datastore.Database)
 	}
 
 	if r.storeState.Collections == nil {
-		r.storeState.Collections = make(map[string]map[string]repositorymodels.Collection)
+		r.storeState.Collections = make(map[string]map[string]datastore.Collection)
 	}
 
 	if r.storeState.Documents == nil {
-		r.storeState.Documents = make(map[string]map[string]map[string]repositorymodels.Document)
+		r.storeState.Documents = make(map[string]map[string]map[string]datastore.Document)
 	}
 
 	if r.storeState.Triggers == nil {
-		r.storeState.Triggers = make(map[string]map[string]map[string]repositorymodels.Trigger)
+		r.storeState.Triggers = make(map[string]map[string]map[string]datastore.Trigger)
 	}
 
 	if r.storeState.StoredProcedures == nil {
-		r.storeState.StoredProcedures = make(map[string]map[string]map[string]repositorymodels.StoredProcedure)
+		r.storeState.StoredProcedures = make(map[string]map[string]map[string]datastore.StoredProcedure)
 	}
 
 	if r.storeState.UserDefinedFunctions == nil {
-		r.storeState.UserDefinedFunctions = make(map[string]map[string]map[string]repositorymodels.UserDefinedFunction)
+		r.storeState.UserDefinedFunctions = make(map[string]map[string]map[string]datastore.UserDefinedFunction)
 	}
 
 	for database := range r.storeState.Databases {
 		if r.storeState.Collections[database] == nil {
-			r.storeState.Collections[database] = make(map[string]repositorymodels.Collection)
+			r.storeState.Collections[database] = make(map[string]datastore.Collection)
 		}
 
 		if r.storeState.Documents[database] == nil {
-			r.storeState.Documents[database] = make(map[string]map[string]repositorymodels.Document)
+			r.storeState.Documents[database] = make(map[string]map[string]datastore.Document)
 		}
 
 		if r.storeState.Triggers[database] == nil {
-			r.storeState.Triggers[database] = make(map[string]map[string]repositorymodels.Trigger)
+			r.storeState.Triggers[database] = make(map[string]map[string]datastore.Trigger)
 		}
 
 		if r.storeState.StoredProcedures[database] == nil {
-			r.storeState.StoredProcedures[database] = make(map[string]map[string]repositorymodels.StoredProcedure)
+			r.storeState.StoredProcedures[database] = make(map[string]map[string]datastore.StoredProcedure)
 		}
 
 		if r.storeState.UserDefinedFunctions[database] == nil {
-			r.storeState.UserDefinedFunctions[database] = make(map[string]map[string]repositorymodels.UserDefinedFunction)
+			r.storeState.UserDefinedFunctions[database] = make(map[string]map[string]datastore.UserDefinedFunction)
 		}
 
 		for collection := range r.storeState.Collections[database] {
 			if r.storeState.Documents[database][collection] == nil {
-				r.storeState.Documents[database][collection] = make(map[string]repositorymodels.Document)
+				r.storeState.Documents[database][collection] = make(map[string]datastore.Document)
 			}
 
 			for document := range r.storeState.Documents[database][collection] {
@@ -191,15 +221,15 @@ func (r *DataRepository) ensureStoreStateNoNullReferences() {
 			}
 
 			if r.storeState.Triggers[database][collection] == nil {
-				r.storeState.Triggers[database][collection] = make(map[string]repositorymodels.Trigger)
+				r.storeState.Triggers[database][collection] = make(map[string]datastore.Trigger)
 			}
 
 			if r.storeState.StoredProcedures[database][collection] == nil {
-				r.storeState.StoredProcedures[database][collection] = make(map[string]repositorymodels.StoredProcedure)
+				r.storeState.StoredProcedures[database][collection] = make(map[string]datastore.StoredProcedure)
 			}
 
 			if r.storeState.UserDefinedFunctions[database][collection] == nil {
-				r.storeState.UserDefinedFunctions[database][collection] = make(map[string]repositorymodels.UserDefinedFunction)
+				r.storeState.UserDefinedFunctions[database][collection] = make(map[string]datastore.UserDefinedFunction)
 			}
 		}
 	}

internal/datastore/map_datastore/stored_procedures.go

@@ -0,0 +1,91 @@
+package mapdatastore
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/internal/resourceid"
+	"golang.org/x/exp/maps"
+)
+
+func (r *MapDataStore) GetAllStoredProcedures(databaseId string, collectionId string) ([]datastore.StoredProcedure, datastore.DataStoreStatus) {
+	r.storeState.RLock()
+	defer r.storeState.RUnlock()
+
+	return maps.Values(r.storeState.StoredProcedures[databaseId][collectionId]), datastore.StatusOk
+}
+
+func (r *MapDataStore) GetStoredProcedure(databaseId string, collectionId string, spId string) (datastore.StoredProcedure, datastore.DataStoreStatus) {
+	r.storeState.RLock()
+	defer r.storeState.RUnlock()
+
+	if _, ok := r.storeState.Databases[databaseId]; !ok {
+		return datastore.StoredProcedure{}, datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.StoredProcedure{}, datastore.StatusNotFound
+	}
+
+	if sp, ok := r.storeState.StoredProcedures[databaseId][collectionId][spId]; ok {
+		return sp, datastore.StatusOk
+	}
+
+	return datastore.StoredProcedure{}, datastore.StatusNotFound
+}
+
+func (r *MapDataStore) DeleteStoredProcedure(databaseId string, collectionId string, spId string) datastore.DataStoreStatus {
+	r.storeState.Lock()
+	defer r.storeState.Unlock()
+
+	if _, ok := r.storeState.Databases[databaseId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.StoredProcedures[databaseId][collectionId][spId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	delete(r.storeState.StoredProcedures[databaseId][collectionId], spId)
+
+	return datastore.StatusOk
+}
+
+func (r *MapDataStore) CreateStoredProcedure(databaseId string, collectionId string, sp datastore.StoredProcedure) (datastore.StoredProcedure, datastore.DataStoreStatus) {
+	r.storeState.Lock()
+	defer r.storeState.Unlock()
+
+	var ok bool
+	var database datastore.Database
+	var collection datastore.Collection
+	if sp.ID == "" {
+		return datastore.StoredProcedure{}, datastore.BadRequest
+	}
+
+	if database, ok = r.storeState.Databases[databaseId]; !ok {
+		return datastore.StoredProcedure{}, datastore.StatusNotFound
+	}
+
+	if collection, ok = r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.StoredProcedure{}, datastore.StatusNotFound
+	}
+
+	if _, ok = r.storeState.StoredProcedures[databaseId][collectionId][sp.ID]; ok {
+		return datastore.StoredProcedure{}, datastore.Conflict
+	}
+
+	sp.TimeStamp = time.Now().Unix()
+	sp.ResourceID = resourceid.NewCombined(collection.ResourceID, resourceid.New(resourceid.ResourceTypeStoredProcedure))
+	sp.ETag = fmt.Sprintf("\"%s\"", uuid.New())
+	sp.Self = fmt.Sprintf("dbs/%s/colls/%s/sprocs/%s/", database.ResourceID, collection.ResourceID, sp.ResourceID)
+
+	r.storeState.StoredProcedures[databaseId][collectionId][sp.ID] = sp
+
+	return sp, datastore.StatusOk
+}

internal/datastore/map_datastore/triggers.go

@@ -1,83 +1,83 @@
-package repositories
+package mapdatastore
 
 import (
 	"fmt"
 	"time"
 
 	"github.com/google/uuid"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/internal/resourceid"
 	"golang.org/x/exp/maps"
 )
 
-func (r *DataRepository) GetAllTriggers(databaseId string, collectionId string) ([]repositorymodels.Trigger, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) GetAllTriggers(databaseId string, collectionId string) ([]datastore.Trigger, datastore.DataStoreStatus) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
-	return maps.Values(r.storeState.Triggers[databaseId][collectionId]), repositorymodels.StatusOk
+	return maps.Values(r.storeState.Triggers[databaseId][collectionId]), datastore.StatusOk
 }
 
-func (r *DataRepository) GetTrigger(databaseId string, collectionId string, triggerId string) (repositorymodels.Trigger, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) GetTrigger(databaseId string, collectionId string, triggerId string) (datastore.Trigger, datastore.DataStoreStatus) {
 	r.storeState.RLock()
 	defer r.storeState.RUnlock()
 
 	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.Trigger{}, repositorymodels.StatusNotFound
+		return datastore.Trigger{}, datastore.StatusNotFound
 	}
 
 	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.Trigger{}, repositorymodels.StatusNotFound
+		return datastore.Trigger{}, datastore.StatusNotFound
 	}
 
 	if trigger, ok := r.storeState.Triggers[databaseId][collectionId][triggerId]; ok {
-		return trigger, repositorymodels.StatusOk
+		return trigger, datastore.StatusOk
 	}
 
-	return repositorymodels.Trigger{}, repositorymodels.StatusNotFound
+	return datastore.Trigger{}, datastore.StatusNotFound
 }
 
-func (r *DataRepository) DeleteTrigger(databaseId string, collectionId string, triggerId string) repositorymodels.RepositoryStatus {
+func (r *MapDataStore) DeleteTrigger(databaseId string, collectionId string, triggerId string) datastore.DataStoreStatus {
 	r.storeState.Lock()
 	defer r.storeState.Unlock()
 
 	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.StatusNotFound
+		return datastore.StatusNotFound
 	}
 
 	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.StatusNotFound
+		return datastore.StatusNotFound
 	}
 
 	if _, ok := r.storeState.Triggers[databaseId][collectionId][triggerId]; !ok {
-		return repositorymodels.StatusNotFound
+		return datastore.StatusNotFound
 	}
 
 	delete(r.storeState.Triggers[databaseId][collectionId], triggerId)
 
-	return repositorymodels.StatusOk
+	return datastore.StatusOk
 }
 
-func (r *DataRepository) CreateTrigger(databaseId string, collectionId string, trigger repositorymodels.Trigger) (repositorymodels.Trigger, repositorymodels.RepositoryStatus) {
+func (r *MapDataStore) CreateTrigger(databaseId string, collectionId string, trigger datastore.Trigger) (datastore.Trigger, datastore.DataStoreStatus) {
 	r.storeState.Lock()
 	defer r.storeState.Unlock()
 
 	var ok bool
-	var database repositorymodels.Database
-	var collection repositorymodels.Collection
+	var database datastore.Database
+	var collection datastore.Collection
 	if trigger.ID == "" {
-		return repositorymodels.Trigger{}, repositorymodels.BadRequest
+		return datastore.Trigger{}, datastore.BadRequest
 	}
 
 	if database, ok = r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.Trigger{}, repositorymodels.StatusNotFound
+		return datastore.Trigger{}, datastore.StatusNotFound
 	}
 
 	if collection, ok = r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.Trigger{}, repositorymodels.StatusNotFound
+		return datastore.Trigger{}, datastore.StatusNotFound
 	}
 
 	if _, ok = r.storeState.Triggers[databaseId][collectionId][trigger.ID]; ok {
-		return repositorymodels.Trigger{}, repositorymodels.Conflict
+		return datastore.Trigger{}, datastore.Conflict
 	}
 
 	trigger.TimeStamp = time.Now().Unix()
@@ -87,5 +87,5 @@ func (r *DataRepository) CreateTrigger(databaseId string, collectionId string, t
 
 	r.storeState.Triggers[databaseId][collectionId][trigger.ID] = trigger
 
-	return trigger, repositorymodels.StatusOk
+	return trigger, datastore.StatusOk
 }

internal/datastore/map_datastore/user_defined_functions.go

@@ -0,0 +1,91 @@
+package mapdatastore
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/internal/resourceid"
+	"golang.org/x/exp/maps"
+)
+
+func (r *MapDataStore) GetAllUserDefinedFunctions(databaseId string, collectionId string) ([]datastore.UserDefinedFunction, datastore.DataStoreStatus) {
+	r.storeState.RLock()
+	defer r.storeState.RUnlock()
+
+	return maps.Values(r.storeState.UserDefinedFunctions[databaseId][collectionId]), datastore.StatusOk
+}
+
+func (r *MapDataStore) GetUserDefinedFunction(databaseId string, collectionId string, udfId string) (datastore.UserDefinedFunction, datastore.DataStoreStatus) {
+	r.storeState.RLock()
+	defer r.storeState.RUnlock()
+
+	if _, ok := r.storeState.Databases[databaseId]; !ok {
+		return datastore.UserDefinedFunction{}, datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.UserDefinedFunction{}, datastore.StatusNotFound
+	}
+
+	if udf, ok := r.storeState.UserDefinedFunctions[databaseId][collectionId][udfId]; ok {
+		return udf, datastore.StatusOk
+	}
+
+	return datastore.UserDefinedFunction{}, datastore.StatusNotFound
+}
+
+func (r *MapDataStore) DeleteUserDefinedFunction(databaseId string, collectionId string, udfId string) datastore.DataStoreStatus {
+	r.storeState.Lock()
+	defer r.storeState.Unlock()
+
+	if _, ok := r.storeState.Databases[databaseId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.UserDefinedFunctions[databaseId][collectionId][udfId]; !ok {
+		return datastore.StatusNotFound
+	}
+
+	delete(r.storeState.UserDefinedFunctions[databaseId][collectionId], udfId)
+
+	return datastore.StatusOk
+}
+
+func (r *MapDataStore) CreateUserDefinedFunction(databaseId string, collectionId string, udf datastore.UserDefinedFunction) (datastore.UserDefinedFunction, datastore.DataStoreStatus) {
+	r.storeState.Lock()
+	defer r.storeState.Unlock()
+
+	var ok bool
+	var database datastore.Database
+	var collection datastore.Collection
+	if udf.ID == "" {
+		return datastore.UserDefinedFunction{}, datastore.BadRequest
+	}
+
+	if database, ok = r.storeState.Databases[databaseId]; !ok {
+		return datastore.UserDefinedFunction{}, datastore.StatusNotFound
+	}
+
+	if collection, ok = r.storeState.Collections[databaseId][collectionId]; !ok {
+		return datastore.UserDefinedFunction{}, datastore.StatusNotFound
+	}
+
+	if _, ok := r.storeState.UserDefinedFunctions[databaseId][collectionId][udf.ID]; ok {
+		return datastore.UserDefinedFunction{}, datastore.Conflict
+	}
+
+	udf.TimeStamp = time.Now().Unix()
+	udf.ResourceID = resourceid.NewCombined(collection.ResourceID, resourceid.New(resourceid.ResourceTypeUserDefinedFunction))
+	udf.ETag = fmt.Sprintf("\"%s\"", uuid.New())
+	udf.Self = fmt.Sprintf("dbs/%s/colls/%s/udfs/%s/", database.ResourceID, collection.ResourceID, udf.ResourceID)
+
+	r.storeState.UserDefinedFunctions[databaseId][collectionId][udf.ID] = udf
+
+	return udf, datastore.StatusOk
+}

internal/datastore/models.go

@@ -1,6 +1,4 @@
-package repositorymodels
-
-import "sync"
+package datastore
 
 type Database struct {
 	ID         string `json:"id"`
@@ -10,13 +8,14 @@ type Database struct {
 	Self       string `json:"_self"`
 }
 
-type RepositoryStatus int
+type DataStoreStatus int
 
 const (
 	StatusOk       = 1
 	StatusNotFound = 2
 	Conflict       = 3
 	BadRequest     = 4
+	IterEOF        = 5
 )
 
 type TriggerOperation string
@@ -117,25 +116,3 @@ type PartitionKeyRange struct {
 	TimeStamp          int64  `json:"_ts"`
 	Lsn                int    `json:"lsn"`
 }
-
-type State struct {
-	sync.RWMutex
-
-	// Map databaseId -> Database
-	Databases map[string]Database `json:"databases"`
-
-	// Map databaseId -> collectionId -> Collection
-	Collections map[string]map[string]Collection `json:"collections"`
-
-	// Map databaseId -> collectionId -> documentId -> Documents
-	Documents map[string]map[string]map[string]Document `json:"documents"`
-
-	// Map databaseId -> collectionId -> triggerId -> Trigger
-	Triggers map[string]map[string]map[string]Trigger `json:"triggers"`
-
-	// Map databaseId -> collectionId -> spId -> StoredProcedure
-	StoredProcedures map[string]map[string]map[string]StoredProcedure `json:"sprocs"`
-
-	// Map databaseId -> collectionId -> udfId -> UserDefinedFunction
-	UserDefinedFunctions map[string]map[string]map[string]UserDefinedFunction `json:"udfs"`
-}

internal/repositories/documents.go

@@ -1,130 +0,0 @@
-package repositories
-
-import (
-	"fmt"
-	"log"
-	"time"
-
-	"github.com/google/uuid"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
-	"github.com/pikami/cosmium/internal/resourceid"
-	"github.com/pikami/cosmium/parsers"
-	"github.com/pikami/cosmium/parsers/nosql"
-	memoryexecutor "github.com/pikami/cosmium/query_executors/memory_executor"
-	"golang.org/x/exp/maps"
-)
-
-func (r *DataRepository) GetAllDocuments(databaseId string, collectionId string) ([]repositorymodels.Document, repositorymodels.RepositoryStatus) {
-	r.storeState.RLock()
-	defer r.storeState.RUnlock()
-
-	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return make([]repositorymodels.Document, 0), repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return make([]repositorymodels.Document, 0), repositorymodels.StatusNotFound
-	}
-
-	return maps.Values(r.storeState.Documents[databaseId][collectionId]), repositorymodels.StatusOk
-}
-
-func (r *DataRepository) GetDocument(databaseId string, collectionId string, documentId string) (repositorymodels.Document, repositorymodels.RepositoryStatus) {
-	r.storeState.RLock()
-	defer r.storeState.RUnlock()
-
-	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.Document{}, repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.Document{}, repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Documents[databaseId][collectionId][documentId]; !ok {
-		return repositorymodels.Document{}, repositorymodels.StatusNotFound
-	}
-
-	return r.storeState.Documents[databaseId][collectionId][documentId], repositorymodels.StatusOk
-}
-
-func (r *DataRepository) DeleteDocument(databaseId string, collectionId string, documentId string) repositorymodels.RepositoryStatus {
-	r.storeState.Lock()
-	defer r.storeState.Unlock()
-
-	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Documents[databaseId][collectionId][documentId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	delete(r.storeState.Documents[databaseId][collectionId], documentId)
-
-	return repositorymodels.StatusOk
-}
-
-func (r *DataRepository) CreateDocument(databaseId string, collectionId string, document map[string]interface{}) (repositorymodels.Document, repositorymodels.RepositoryStatus) {
-	r.storeState.Lock()
-	defer r.storeState.Unlock()
-
-	var ok bool
-	var documentId string
-	var database repositorymodels.Database
-	var collection repositorymodels.Collection
-	if documentId, ok = document["id"].(string); !ok || documentId == "" {
-		documentId = fmt.Sprint(uuid.New())
-		document["id"] = documentId
-	}
-
-	if database, ok = r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.Document{}, repositorymodels.StatusNotFound
-	}
-
-	if collection, ok = r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.Document{}, repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Documents[databaseId][collectionId][documentId]; ok {
-		return repositorymodels.Document{}, repositorymodels.Conflict
-	}
-
-	document["_ts"] = time.Now().Unix()
-	document["_rid"] = resourceid.NewCombined(collection.ResourceID, resourceid.New(resourceid.ResourceTypeDocument))
-	document["_etag"] = fmt.Sprintf("\"%s\"", uuid.New())
-	document["_self"] = fmt.Sprintf("dbs/%s/colls/%s/docs/%s/", database.ResourceID, collection.ResourceID, document["_rid"])
-
-	r.storeState.Documents[databaseId][collectionId][documentId] = document
-
-	return document, repositorymodels.StatusOk
-}
-
-func (r *DataRepository) ExecuteQueryDocuments(databaseId string, collectionId string, query string, queryParameters map[string]interface{}) ([]memoryexecutor.RowType, repositorymodels.RepositoryStatus) {
-	parsedQuery, err := nosql.Parse("", []byte(query))
-	if err != nil {
-		log.Printf("Failed to parse query: %s\nerr: %v", query, err)
-		return nil, repositorymodels.BadRequest
-	}
-
-	collectionDocuments, status := r.GetAllDocuments(databaseId, collectionId)
-	if status != repositorymodels.StatusOk {
-		return nil, status
-	}
-
-	covDocs := make([]memoryexecutor.RowType, 0)
-	for _, doc := range collectionDocuments {
-		covDocs = append(covDocs, map[string]interface{}(doc))
-	}
-
-	if typedQuery, ok := parsedQuery.(parsers.SelectStmt); ok {
-		typedQuery.Parameters = queryParameters
-		return memoryexecutor.ExecuteQuery(typedQuery, covDocs), repositorymodels.StatusOk
-	}
-
-	return nil, repositorymodels.BadRequest
-}

internal/repositories/repositories.go

@@ -1,34 +0,0 @@
-package repositories
-
-import repositorymodels "github.com/pikami/cosmium/internal/repository_models"
-
-type DataRepository struct {
-	storeState repositorymodels.State
-
-	initialDataFilePath string
-	persistDataFilePath string
-}
-
-type RepositoryOptions struct {
-	InitialDataFilePath string
-	PersistDataFilePath string
-}
-
-func NewDataRepository(options RepositoryOptions) *DataRepository {
-	repository := &DataRepository{
-		storeState: repositorymodels.State{
-			Databases:            make(map[string]repositorymodels.Database),
-			Collections:          make(map[string]map[string]repositorymodels.Collection),
-			Documents:            make(map[string]map[string]map[string]repositorymodels.Document),
-			Triggers:             make(map[string]map[string]map[string]repositorymodels.Trigger),
-			StoredProcedures:     make(map[string]map[string]map[string]repositorymodels.StoredProcedure),
-			UserDefinedFunctions: make(map[string]map[string]map[string]repositorymodels.UserDefinedFunction),
-		},
-		initialDataFilePath: options.InitialDataFilePath,
-		persistDataFilePath: options.PersistDataFilePath,
-	}
-
-	repository.InitializeRepository()
-
-	return repository
-}

internal/repositories/stored_procedures.go

@@ -1,91 +0,0 @@
-package repositories
-
-import (
-	"fmt"
-	"time"
-
-	"github.com/google/uuid"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
-	"github.com/pikami/cosmium/internal/resourceid"
-	"golang.org/x/exp/maps"
-)
-
-func (r *DataRepository) GetAllStoredProcedures(databaseId string, collectionId string) ([]repositorymodels.StoredProcedure, repositorymodels.RepositoryStatus) {
-	r.storeState.RLock()
-	defer r.storeState.RUnlock()
-
-	return maps.Values(r.storeState.StoredProcedures[databaseId][collectionId]), repositorymodels.StatusOk
-}
-
-func (r *DataRepository) GetStoredProcedure(databaseId string, collectionId string, spId string) (repositorymodels.StoredProcedure, repositorymodels.RepositoryStatus) {
-	r.storeState.RLock()
-	defer r.storeState.RUnlock()
-
-	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.StoredProcedure{}, repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.StoredProcedure{}, repositorymodels.StatusNotFound
-	}
-
-	if sp, ok := r.storeState.StoredProcedures[databaseId][collectionId][spId]; ok {
-		return sp, repositorymodels.StatusOk
-	}
-
-	return repositorymodels.StoredProcedure{}, repositorymodels.StatusNotFound
-}
-
-func (r *DataRepository) DeleteStoredProcedure(databaseId string, collectionId string, spId string) repositorymodels.RepositoryStatus {
-	r.storeState.Lock()
-	defer r.storeState.Unlock()
-
-	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.StoredProcedures[databaseId][collectionId][spId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	delete(r.storeState.StoredProcedures[databaseId][collectionId], spId)
-
-	return repositorymodels.StatusOk
-}
-
-func (r *DataRepository) CreateStoredProcedure(databaseId string, collectionId string, sp repositorymodels.StoredProcedure) (repositorymodels.StoredProcedure, repositorymodels.RepositoryStatus) {
-	r.storeState.Lock()
-	defer r.storeState.Unlock()
-
-	var ok bool
-	var database repositorymodels.Database
-	var collection repositorymodels.Collection
-	if sp.ID == "" {
-		return repositorymodels.StoredProcedure{}, repositorymodels.BadRequest
-	}
-
-	if database, ok = r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.StoredProcedure{}, repositorymodels.StatusNotFound
-	}
-
-	if collection, ok = r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.StoredProcedure{}, repositorymodels.StatusNotFound
-	}
-
-	if _, ok = r.storeState.StoredProcedures[databaseId][collectionId][sp.ID]; ok {
-		return repositorymodels.StoredProcedure{}, repositorymodels.Conflict
-	}
-
-	sp.TimeStamp = time.Now().Unix()
-	sp.ResourceID = resourceid.NewCombined(collection.ResourceID, resourceid.New(resourceid.ResourceTypeStoredProcedure))
-	sp.ETag = fmt.Sprintf("\"%s\"", uuid.New())
-	sp.Self = fmt.Sprintf("dbs/%s/colls/%s/sprocs/%s/", database.ResourceID, collection.ResourceID, sp.ResourceID)
-
-	r.storeState.StoredProcedures[databaseId][collectionId][sp.ID] = sp
-
-	return sp, repositorymodels.StatusOk
-}

internal/repositories/user_defined_functions.go

@@ -1,91 +0,0 @@
-package repositories
-
-import (
-	"fmt"
-	"time"
-
-	"github.com/google/uuid"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
-	"github.com/pikami/cosmium/internal/resourceid"
-	"golang.org/x/exp/maps"
-)
-
-func (r *DataRepository) GetAllUserDefinedFunctions(databaseId string, collectionId string) ([]repositorymodels.UserDefinedFunction, repositorymodels.RepositoryStatus) {
-	r.storeState.RLock()
-	defer r.storeState.RUnlock()
-
-	return maps.Values(r.storeState.UserDefinedFunctions[databaseId][collectionId]), repositorymodels.StatusOk
-}
-
-func (r *DataRepository) GetUserDefinedFunction(databaseId string, collectionId string, udfId string) (repositorymodels.UserDefinedFunction, repositorymodels.RepositoryStatus) {
-	r.storeState.RLock()
-	defer r.storeState.RUnlock()
-
-	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.UserDefinedFunction{}, repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.UserDefinedFunction{}, repositorymodels.StatusNotFound
-	}
-
-	if udf, ok := r.storeState.UserDefinedFunctions[databaseId][collectionId][udfId]; ok {
-		return udf, repositorymodels.StatusOk
-	}
-
-	return repositorymodels.UserDefinedFunction{}, repositorymodels.StatusNotFound
-}
-
-func (r *DataRepository) DeleteUserDefinedFunction(databaseId string, collectionId string, udfId string) repositorymodels.RepositoryStatus {
-	r.storeState.Lock()
-	defer r.storeState.Unlock()
-
-	if _, ok := r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.UserDefinedFunctions[databaseId][collectionId][udfId]; !ok {
-		return repositorymodels.StatusNotFound
-	}
-
-	delete(r.storeState.UserDefinedFunctions[databaseId][collectionId], udfId)
-
-	return repositorymodels.StatusOk
-}
-
-func (r *DataRepository) CreateUserDefinedFunction(databaseId string, collectionId string, udf repositorymodels.UserDefinedFunction) (repositorymodels.UserDefinedFunction, repositorymodels.RepositoryStatus) {
-	r.storeState.Lock()
-	defer r.storeState.Unlock()
-
-	var ok bool
-	var database repositorymodels.Database
-	var collection repositorymodels.Collection
-	if udf.ID == "" {
-		return repositorymodels.UserDefinedFunction{}, repositorymodels.BadRequest
-	}
-
-	if database, ok = r.storeState.Databases[databaseId]; !ok {
-		return repositorymodels.UserDefinedFunction{}, repositorymodels.StatusNotFound
-	}
-
-	if collection, ok = r.storeState.Collections[databaseId][collectionId]; !ok {
-		return repositorymodels.UserDefinedFunction{}, repositorymodels.StatusNotFound
-	}
-
-	if _, ok := r.storeState.UserDefinedFunctions[databaseId][collectionId][udf.ID]; ok {
-		return repositorymodels.UserDefinedFunction{}, repositorymodels.Conflict
-	}
-
-	udf.TimeStamp = time.Now().Unix()
-	udf.ResourceID = resourceid.NewCombined(collection.ResourceID, resourceid.New(resourceid.ResourceTypeUserDefinedFunction))
-	udf.ETag = fmt.Sprintf("\"%s\"", uuid.New())
-	udf.Self = fmt.Sprintf("dbs/%s/colls/%s/udfs/%s/", database.ResourceID, collection.ResourceID, udf.ResourceID)
-
-	r.storeState.UserDefinedFunctions[databaseId][collectionId][udf.ID] = udf
-
-	return udf, repositorymodels.StatusOk
-}

internal/struct_hidrators/collection_defaults.go

@@ -1,21 +1,19 @@
 package structhidrators
 
-import (
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
-)
+import "github.com/pikami/cosmium/internal/datastore"
 
-var defaultCollection repositorymodels.Collection = repositorymodels.Collection{
-	IndexingPolicy: repositorymodels.CollectionIndexingPolicy{
+var defaultCollection datastore.Collection = datastore.Collection{
+	IndexingPolicy: datastore.CollectionIndexingPolicy{
 		IndexingMode: "consistent",
 		Automatic:    true,
-		IncludedPaths: []repositorymodels.CollectionIndexingPolicyPath{
+		IncludedPaths: []datastore.CollectionIndexingPolicyPath{
 			{Path: "/*"},
 		},
-		ExcludedPaths: []repositorymodels.CollectionIndexingPolicyPath{
+		ExcludedPaths: []datastore.CollectionIndexingPolicyPath{
 			{Path: "/\"_etag\"/?"},
 		},
 	},
-	PartitionKey: repositorymodels.CollectionPartitionKey{
+	PartitionKey: datastore.CollectionPartitionKey{
 		Paths:   []string{"/_partitionKey"},
 		Kind:    "Hash",
 		Version: 2,

internal/struct_hidrators/hidrate.go

@@ -3,11 +3,11 @@ package structhidrators
 import (
 	"reflect"
 
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 func Hidrate(input interface{}) interface{} {
-	if reflect.TypeOf(input) == reflect.TypeOf(repositorymodels.Collection{}) {
+	if reflect.TypeOf(input) == reflect.TypeOf(datastore.Collection{}) {
 		return hidrate(input, defaultCollection)
 	}
 	return input

query_executors/memory_executor/array_functions.go

@@ -196,6 +196,10 @@ func (r rowContext) parseArray(argument interface{}) []interface{} {
 	ex := r.resolveSelectItem(exItem)
 
 	arrValue := reflect.ValueOf(ex)
+	if arrValue.Kind() == reflect.Invalid {
+		return nil
+	}
+
 	if arrValue.Kind() != reflect.Slice {
 		logger.ErrorLn("parseArray got parameters of wrong type")
 		return nil

query_executors/memory_executor/array_iterator.go

@@ -0,0 +1,27 @@
+package memoryexecutor
+
+import "github.com/pikami/cosmium/internal/datastore"
+
+type rowArrayIterator struct {
+	documents []rowContext
+	index     int
+}
+
+func NewRowArrayIterator(documents []rowContext) *rowArrayIterator {
+	return &rowArrayIterator{
+		documents: documents,
+		index:     -1,
+	}
+}
+
+func (i *rowArrayIterator) Next() (rowContext, datastore.DataStoreStatus) {
+	i.index++
+	if i.index >= len(i.documents) {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	row := i.documents[i.index]
+	i.documents[i.index] = rowContext{} // Help GC reclaim memory
+
+	return row, datastore.StatusOk
+}

query_executors/memory_executor/common.go

@@ -0,0 +1,397 @@
+package memoryexecutor
+
+import (
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/internal/logger"
+	"github.com/pikami/cosmium/parsers"
+)
+
+type RowType interface{}
+type rowContext struct {
+	tables       map[string]RowType
+	parameters   map[string]interface{}
+	grouppedRows []rowContext
+}
+
+type rowIterator interface {
+	Next() (rowContext, datastore.DataStoreStatus)
+}
+
+type rowTypeIterator interface {
+	Next() (RowType, datastore.DataStoreStatus)
+}
+
+func resolveDestinationColumnName(selectItem parsers.SelectItem, itemIndex int, queryParameters map[string]interface{}) string {
+	if selectItem.Alias != "" {
+		return selectItem.Alias
+	}
+
+	destinationName := fmt.Sprintf("$%d", itemIndex+1)
+	if len(selectItem.Path) > 0 {
+		destinationName = selectItem.Path[len(selectItem.Path)-1]
+	}
+
+	if destinationName[0] == '@' {
+		destinationName = queryParameters[destinationName].(string)
+	}
+
+	return destinationName
+}
+
+func (r rowContext) resolveSelectItem(selectItem parsers.SelectItem) interface{} {
+	if selectItem.Type == parsers.SelectItemTypeArray {
+		return r.selectItem_SelectItemTypeArray(selectItem)
+	}
+
+	if selectItem.Type == parsers.SelectItemTypeObject {
+		return r.selectItem_SelectItemTypeObject(selectItem)
+	}
+
+	if selectItem.Type == parsers.SelectItemTypeConstant {
+		return r.selectItem_SelectItemTypeConstant(selectItem)
+	}
+
+	if selectItem.Type == parsers.SelectItemTypeSubQuery {
+		return r.selectItem_SelectItemTypeSubQuery(selectItem)
+	}
+
+	if selectItem.Type == parsers.SelectItemTypeFunctionCall {
+		if typedFunctionCall, ok := selectItem.Value.(parsers.FunctionCall); ok {
+			return r.selectItem_SelectItemTypeFunctionCall(typedFunctionCall)
+		}
+
+		logger.ErrorLn("parsers.SelectItem has incorrect Value type (expected parsers.FunctionCall)")
+		return nil
+	}
+
+	return r.selectItem_SelectItemTypeField(selectItem)
+}
+
+func (r rowContext) selectItem_SelectItemTypeArray(selectItem parsers.SelectItem) interface{} {
+	arrayValue := make([]interface{}, 0)
+	for _, subSelectItem := range selectItem.SelectItems {
+		arrayValue = append(arrayValue, r.resolveSelectItem(subSelectItem))
+	}
+	return arrayValue
+}
+
+func (r rowContext) selectItem_SelectItemTypeObject(selectItem parsers.SelectItem) interface{} {
+	objectValue := make(map[string]interface{})
+	for _, subSelectItem := range selectItem.SelectItems {
+		objectValue[subSelectItem.Alias] = r.resolveSelectItem(subSelectItem)
+	}
+	return objectValue
+}
+
+func (r rowContext) selectItem_SelectItemTypeConstant(selectItem parsers.SelectItem) interface{} {
+	var typedValue parsers.Constant
+	var ok bool
+	if typedValue, ok = selectItem.Value.(parsers.Constant); !ok {
+		// TODO: Handle error
+		logger.ErrorLn("parsers.Constant has incorrect Value type")
+	}
+
+	if typedValue.Type == parsers.ConstantTypeParameterConstant &&
+		r.parameters != nil {
+		if key, ok := typedValue.Value.(string); ok {
+			return r.parameters[key]
+		}
+	}
+
+	return typedValue.Value
+}
+
+func (r rowContext) selectItem_SelectItemTypeSubQuery(selectItem parsers.SelectItem) interface{} {
+	subQuery := selectItem.Value.(parsers.SelectStmt)
+	subQueryResult := executeQuery(
+		subQuery,
+		NewRowArrayIterator([]rowContext{r}),
+	)
+
+	if subQuery.Exists {
+		_, status := subQueryResult.Next()
+		return status == datastore.StatusOk
+	}
+
+	allDocuments := make([]RowType, 0)
+	for {
+		row, status := subQueryResult.Next()
+		if status != datastore.StatusOk {
+			break
+		}
+		allDocuments = append(allDocuments, row)
+	}
+
+	return allDocuments
+}
+
+func (r rowContext) selectItem_SelectItemTypeFunctionCall(functionCall parsers.FunctionCall) interface{} {
+	switch functionCall.Type {
+	case parsers.FunctionCallStringEquals:
+		return r.strings_StringEquals(functionCall.Arguments)
+	case parsers.FunctionCallContains:
+		return r.strings_Contains(functionCall.Arguments)
+	case parsers.FunctionCallEndsWith:
+		return r.strings_EndsWith(functionCall.Arguments)
+	case parsers.FunctionCallStartsWith:
+		return r.strings_StartsWith(functionCall.Arguments)
+	case parsers.FunctionCallConcat:
+		return r.strings_Concat(functionCall.Arguments)
+	case parsers.FunctionCallIndexOf:
+		return r.strings_IndexOf(functionCall.Arguments)
+	case parsers.FunctionCallToString:
+		return r.strings_ToString(functionCall.Arguments)
+	case parsers.FunctionCallUpper:
+		return r.strings_Upper(functionCall.Arguments)
+	case parsers.FunctionCallLower:
+		return r.strings_Lower(functionCall.Arguments)
+	case parsers.FunctionCallLeft:
+		return r.strings_Left(functionCall.Arguments)
+	case parsers.FunctionCallLength:
+		return r.strings_Length(functionCall.Arguments)
+	case parsers.FunctionCallLTrim:
+		return r.strings_LTrim(functionCall.Arguments)
+	case parsers.FunctionCallReplace:
+		return r.strings_Replace(functionCall.Arguments)
+	case parsers.FunctionCallReplicate:
+		return r.strings_Replicate(functionCall.Arguments)
+	case parsers.FunctionCallReverse:
+		return r.strings_Reverse(functionCall.Arguments)
+	case parsers.FunctionCallRight:
+		return r.strings_Right(functionCall.Arguments)
+	case parsers.FunctionCallRTrim:
+		return r.strings_RTrim(functionCall.Arguments)
+	case parsers.FunctionCallSubstring:
+		return r.strings_Substring(functionCall.Arguments)
+	case parsers.FunctionCallTrim:
+		return r.strings_Trim(functionCall.Arguments)
+
+	case parsers.FunctionCallIsDefined:
+		return r.typeChecking_IsDefined(functionCall.Arguments)
+	case parsers.FunctionCallIsArray:
+		return r.typeChecking_IsArray(functionCall.Arguments)
+	case parsers.FunctionCallIsBool:
+		return r.typeChecking_IsBool(functionCall.Arguments)
+	case parsers.FunctionCallIsFiniteNumber:
+		return r.typeChecking_IsFiniteNumber(functionCall.Arguments)
+	case parsers.FunctionCallIsInteger:
+		return r.typeChecking_IsInteger(functionCall.Arguments)
+	case parsers.FunctionCallIsNull:
+		return r.typeChecking_IsNull(functionCall.Arguments)
+	case parsers.FunctionCallIsNumber:
+		return r.typeChecking_IsNumber(functionCall.Arguments)
+	case parsers.FunctionCallIsObject:
+		return r.typeChecking_IsObject(functionCall.Arguments)
+	case parsers.FunctionCallIsPrimitive:
+		return r.typeChecking_IsPrimitive(functionCall.Arguments)
+	case parsers.FunctionCallIsString:
+		return r.typeChecking_IsString(functionCall.Arguments)
+
+	case parsers.FunctionCallArrayConcat:
+		return r.array_Concat(functionCall.Arguments)
+	case parsers.FunctionCallArrayContains:
+		return r.array_Contains(functionCall.Arguments)
+	case parsers.FunctionCallArrayContainsAny:
+		return r.array_Contains_Any(functionCall.Arguments)
+	case parsers.FunctionCallArrayContainsAll:
+		return r.array_Contains_All(functionCall.Arguments)
+	case parsers.FunctionCallArrayLength:
+		return r.array_Length(functionCall.Arguments)
+	case parsers.FunctionCallArraySlice:
+		return r.array_Slice(functionCall.Arguments)
+	case parsers.FunctionCallSetIntersect:
+		return r.set_Intersect(functionCall.Arguments)
+	case parsers.FunctionCallSetUnion:
+		return r.set_Union(functionCall.Arguments)
+
+	case parsers.FunctionCallMathAbs:
+		return r.math_Abs(functionCall.Arguments)
+	case parsers.FunctionCallMathAcos:
+		return r.math_Acos(functionCall.Arguments)
+	case parsers.FunctionCallMathAsin:
+		return r.math_Asin(functionCall.Arguments)
+	case parsers.FunctionCallMathAtan:
+		return r.math_Atan(functionCall.Arguments)
+	case parsers.FunctionCallMathCeiling:
+		return r.math_Ceiling(functionCall.Arguments)
+	case parsers.FunctionCallMathCos:
+		return r.math_Cos(functionCall.Arguments)
+	case parsers.FunctionCallMathCot:
+		return r.math_Cot(functionCall.Arguments)
+	case parsers.FunctionCallMathDegrees:
+		return r.math_Degrees(functionCall.Arguments)
+	case parsers.FunctionCallMathExp:
+		return r.math_Exp(functionCall.Arguments)
+	case parsers.FunctionCallMathFloor:
+		return r.math_Floor(functionCall.Arguments)
+	case parsers.FunctionCallMathIntBitNot:
+		return r.math_IntBitNot(functionCall.Arguments)
+	case parsers.FunctionCallMathLog10:
+		return r.math_Log10(functionCall.Arguments)
+	case parsers.FunctionCallMathRadians:
+		return r.math_Radians(functionCall.Arguments)
+	case parsers.FunctionCallMathRound:
+		return r.math_Round(functionCall.Arguments)
+	case parsers.FunctionCallMathSign:
+		return r.math_Sign(functionCall.Arguments)
+	case parsers.FunctionCallMathSin:
+		return r.math_Sin(functionCall.Arguments)
+	case parsers.FunctionCallMathSqrt:
+		return r.math_Sqrt(functionCall.Arguments)
+	case parsers.FunctionCallMathSquare:
+		return r.math_Square(functionCall.Arguments)
+	case parsers.FunctionCallMathTan:
+		return r.math_Tan(functionCall.Arguments)
+	case parsers.FunctionCallMathTrunc:
+		return r.math_Trunc(functionCall.Arguments)
+	case parsers.FunctionCallMathAtn2:
+		return r.math_Atn2(functionCall.Arguments)
+	case parsers.FunctionCallMathIntAdd:
+		return r.math_IntAdd(functionCall.Arguments)
+	case parsers.FunctionCallMathIntBitAnd:
+		return r.math_IntBitAnd(functionCall.Arguments)
+	case parsers.FunctionCallMathIntBitLeftShift:
+		return r.math_IntBitLeftShift(functionCall.Arguments)
+	case parsers.FunctionCallMathIntBitOr:
+		return r.math_IntBitOr(functionCall.Arguments)
+	case parsers.FunctionCallMathIntBitRightShift:
+		return r.math_IntBitRightShift(functionCall.Arguments)
+	case parsers.FunctionCallMathIntBitXor:
+		return r.math_IntBitXor(functionCall.Arguments)
+	case parsers.FunctionCallMathIntDiv:
+		return r.math_IntDiv(functionCall.Arguments)
+	case parsers.FunctionCallMathIntMod:
+		return r.math_IntMod(functionCall.Arguments)
+	case parsers.FunctionCallMathIntMul:
+		return r.math_IntMul(functionCall.Arguments)
+	case parsers.FunctionCallMathIntSub:
+		return r.math_IntSub(functionCall.Arguments)
+	case parsers.FunctionCallMathPower:
+		return r.math_Power(functionCall.Arguments)
+	case parsers.FunctionCallMathLog:
+		return r.math_Log(functionCall.Arguments)
+	case parsers.FunctionCallMathNumberBin:
+		return r.math_NumberBin(functionCall.Arguments)
+	case parsers.FunctionCallMathPi:
+		return r.math_Pi()
+	case parsers.FunctionCallMathRand:
+		return r.math_Rand()
+
+	case parsers.FunctionCallAggregateAvg:
+		return r.aggregate_Avg(functionCall.Arguments)
+	case parsers.FunctionCallAggregateCount:
+		return r.aggregate_Count(functionCall.Arguments)
+	case parsers.FunctionCallAggregateMax:
+		return r.aggregate_Max(functionCall.Arguments)
+	case parsers.FunctionCallAggregateMin:
+		return r.aggregate_Min(functionCall.Arguments)
+	case parsers.FunctionCallAggregateSum:
+		return r.aggregate_Sum(functionCall.Arguments)
+
+	case parsers.FunctionCallIn:
+		return r.misc_In(functionCall.Arguments)
+	}
+
+	logger.Errorf("Unknown function call type: %v", functionCall.Type)
+	return nil
+}
+
+func (r rowContext) selectItem_SelectItemTypeField(selectItem parsers.SelectItem) interface{} {
+	value := r.tables[selectItem.Path[0]]
+
+	if len(selectItem.Path) > 1 {
+		for _, pathSegment := range selectItem.Path[1:] {
+			if pathSegment[0] == '@' {
+				pathSegment = r.parameters[pathSegment].(string)
+			}
+
+			switch nestedValue := value.(type) {
+			case map[string]interface{}:
+				value = nestedValue[pathSegment]
+			case map[string]RowType:
+				value = nestedValue[pathSegment]
+			case datastore.Document:
+				value = nestedValue[pathSegment]
+			case map[string]datastore.Document:
+				value = nestedValue[pathSegment]
+			case []int, []string, []interface{}:
+				slice := reflect.ValueOf(nestedValue)
+				if arrayIndex, err := strconv.Atoi(pathSegment); err == nil && slice.Len() > arrayIndex {
+					value = slice.Index(arrayIndex).Interface()
+				} else {
+					return nil
+				}
+			default:
+				return nil
+			}
+		}
+	}
+
+	return value
+}
+
+func compareValues(val1, val2 interface{}) int {
+	if val1 == nil && val2 == nil {
+		return 0
+	} else if val1 == nil {
+		return -1
+	} else if val2 == nil {
+		return 1
+	}
+
+	if reflect.TypeOf(val1) != reflect.TypeOf(val2) {
+		return 1
+	}
+
+	switch val1 := val1.(type) {
+	case int:
+		val2 := val2.(int)
+		if val1 < val2 {
+			return -1
+		} else if val1 > val2 {
+			return 1
+		}
+		return 0
+	case float64:
+		val2 := val2.(float64)
+		if val1 < val2 {
+			return -1
+		} else if val1 > val2 {
+			return 1
+		}
+		return 0
+	case string:
+		val2 := val2.(string)
+		return strings.Compare(val1, val2)
+	case bool:
+		val2 := val2.(bool)
+		if val1 == val2 {
+			return 0
+		} else if val1 {
+			return 1
+		} else {
+			return -1
+		}
+	// TODO: Add more types
+	default:
+		if reflect.DeepEqual(val1, val2) {
+			return 0
+		}
+		return 1
+	}
+}
+
+func copyMap[T RowType | []RowType](originalMap map[string]T) map[string]T {
+	targetMap := make(map[string]T)
+
+	for k, v := range originalMap {
+		targetMap[k] = v
+	}
+
+	return targetMap
+}

query_executors/memory_executor/distinct_iterator.go

@@ -0,0 +1,36 @@
+package memoryexecutor
+
+import "github.com/pikami/cosmium/internal/datastore"
+
+type distinctIterator struct {
+	documents rowTypeIterator
+	seenDocs  []RowType
+}
+
+func (di *distinctIterator) Next() (RowType, datastore.DataStoreStatus) {
+	if di.documents == nil {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	for {
+		row, status := di.documents.Next()
+		if status != datastore.StatusOk {
+			di.documents = nil
+			return rowContext{}, status
+		}
+
+		if !di.seen(row) {
+			di.seenDocs = append(di.seenDocs, row)
+			return row, status
+		}
+	}
+}
+
+func (di *distinctIterator) seen(row RowType) bool {
+	for _, seenRow := range di.seenDocs {
+		if compareValues(seenRow, row) == 0 {
+			return true
+		}
+	}
+	return false
+}

query_executors/memory_executor/filter_iterator.go

@@ -0,0 +1,143 @@
+package memoryexecutor
+
+import (
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/internal/logger"
+	"github.com/pikami/cosmium/parsers"
+)
+
+type filterIterator struct {
+	documents rowIterator
+	filters   interface{}
+}
+
+func (fi *filterIterator) Next() (rowContext, datastore.DataStoreStatus) {
+	if fi.documents == nil {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	for {
+		row, status := fi.documents.Next()
+		if status != datastore.StatusOk {
+			fi.documents = nil
+			return rowContext{}, status
+		}
+
+		if fi.evaluateFilters(row) {
+			return row, status
+		}
+	}
+}
+
+func (fi *filterIterator) evaluateFilters(row rowContext) bool {
+	if fi.filters == nil {
+		return true
+	}
+
+	switch typedFilters := fi.filters.(type) {
+	case parsers.ComparisonExpression:
+		return row.filters_ComparisonExpression(typedFilters)
+	case parsers.LogicalExpression:
+		return row.filters_LogicalExpression(typedFilters)
+	case parsers.Constant:
+		if value, ok := typedFilters.Value.(bool); ok {
+			return value
+		}
+		return false
+	case parsers.SelectItem:
+		resolvedValue := row.resolveSelectItem(typedFilters)
+		if value, ok := resolvedValue.(bool); ok {
+			if typedFilters.Invert {
+				return !value
+			}
+
+			return value
+		}
+	}
+
+	return false
+}
+
+func (r rowContext) applyFilters(filters interface{}) bool {
+	if filters == nil {
+		return true
+	}
+
+	switch typedFilters := filters.(type) {
+	case parsers.ComparisonExpression:
+		return r.filters_ComparisonExpression(typedFilters)
+	case parsers.LogicalExpression:
+		return r.filters_LogicalExpression(typedFilters)
+	case parsers.Constant:
+		if value, ok := typedFilters.Value.(bool); ok {
+			return value
+		}
+		return false
+	case parsers.SelectItem:
+		resolvedValue := r.resolveSelectItem(typedFilters)
+		if value, ok := resolvedValue.(bool); ok {
+			if typedFilters.Invert {
+				return !value
+			}
+
+			return value
+		}
+	}
+
+	return false
+}
+
+func (r rowContext) filters_ComparisonExpression(expression parsers.ComparisonExpression) bool {
+	leftExpression, leftExpressionOk := expression.Left.(parsers.SelectItem)
+	rightExpression, rightExpressionOk := expression.Right.(parsers.SelectItem)
+
+	if !leftExpressionOk || !rightExpressionOk {
+		logger.ErrorLn("ComparisonExpression has incorrect Left or Right type")
+		return false
+	}
+
+	leftValue := r.resolveSelectItem(leftExpression)
+	rightValue := r.resolveSelectItem(rightExpression)
+
+	cmp := compareValues(leftValue, rightValue)
+	switch expression.Operation {
+	case "=":
+		return cmp == 0
+	case "!=":
+		return cmp != 0
+	case "<":
+		return cmp < 0
+	case ">":
+		return cmp > 0
+	case "<=":
+		return cmp <= 0
+	case ">=":
+		return cmp >= 0
+	}
+
+	return false
+}
+
+func (r rowContext) filters_LogicalExpression(expression parsers.LogicalExpression) bool {
+	var result bool
+	for i, subExpression := range expression.Expressions {
+		expressionResult := r.applyFilters(subExpression)
+		if i == 0 {
+			result = expressionResult
+		}
+
+		switch expression.Operation {
+		case parsers.LogicalExpressionTypeAnd:
+			result = result && expressionResult
+			if !result {
+				return false
+			}
+		case parsers.LogicalExpressionTypeOr:
+			result = result || expressionResult
+			if result {
+				return true
+			}
+		}
+	}
+	return result
+}

query_executors/memory_executor/from_iterator.go

@@ -0,0 +1,73 @@
+package memoryexecutor
+
+import (
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/parsers"
+)
+
+type fromIterator struct {
+	documents   rowIterator
+	table       parsers.Table
+	buffer      []rowContext
+	bufferIndex int
+}
+
+func (fi *fromIterator) Next() (rowContext, datastore.DataStoreStatus) {
+	if fi.documents == nil {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	// Return from buffer if available
+	if fi.bufferIndex < len(fi.buffer) {
+		result := fi.buffer[fi.bufferIndex]
+		fi.buffer[fi.bufferIndex] = rowContext{}
+		fi.bufferIndex++
+		return result, datastore.StatusOk
+	}
+
+	// Resolve next row from documents
+	row, status := fi.documents.Next()
+	if status != datastore.StatusOk {
+		fi.documents = nil
+		return row, status
+	}
+
+	if fi.table.SelectItem.Path != nil || fi.table.SelectItem.Type == parsers.SelectItemTypeSubQuery {
+		destinationTableName := fi.table.SelectItem.Alias
+		if destinationTableName == "" {
+			destinationTableName = fi.table.Value
+		}
+		if destinationTableName == "" {
+			destinationTableName = resolveDestinationColumnName(fi.table.SelectItem, 0, row.parameters)
+		}
+
+		if fi.table.IsInSelect || fi.table.SelectItem.Type == parsers.SelectItemTypeSubQuery {
+			selectValue := row.parseArray(fi.table.SelectItem)
+			rowContexts := make([]rowContext, len(selectValue))
+			for i, newRowData := range selectValue {
+				rowContexts[i].parameters = row.parameters
+				rowContexts[i].tables = copyMap(row.tables)
+				rowContexts[i].tables[destinationTableName] = newRowData
+			}
+
+			fi.buffer = rowContexts
+			fi.bufferIndex = 0
+			return fi.Next()
+		}
+
+		if len(fi.table.SelectItem.Path) > 0 {
+			sourceTableName := fi.table.SelectItem.Path[0]
+			sourceTableData := row.tables[sourceTableName]
+			if sourceTableData == nil {
+				// When source table is not found, assume it's root document
+				row.tables[sourceTableName] = row.tables["$root"]
+			}
+		}
+
+		newRowData := row.resolveSelectItem(fi.table.SelectItem)
+		row.tables[destinationTableName] = newRowData
+		return row, status
+	}
+
+	return row, status
+}

query_executors/memory_executor/groupBy_iterator.go

@@ -0,0 +1,69 @@
+package memoryexecutor
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/parsers"
+)
+
+type groupByIterator struct {
+	documents   rowIterator
+	groupBy     []parsers.SelectItem
+	groupedRows []rowContext
+}
+
+func (gi *groupByIterator) Next() (rowContext, datastore.DataStoreStatus) {
+	if gi.groupedRows != nil {
+		if len(gi.groupedRows) == 0 {
+			return rowContext{}, datastore.IterEOF
+		}
+		row := gi.groupedRows[0]
+		gi.groupedRows = gi.groupedRows[1:]
+		return row, datastore.StatusOk
+	}
+
+	documents := make([]rowContext, 0)
+	for {
+		row, status := gi.documents.Next()
+		if status != datastore.StatusOk {
+			break
+		}
+
+		documents = append(documents, row)
+	}
+	gi.documents = nil
+
+	groupedRows := make(map[string][]rowContext)
+	groupedKeys := make([]string, 0)
+
+	for _, row := range documents {
+		key := row.generateGroupByKey(gi.groupBy)
+		if _, ok := groupedRows[key]; !ok {
+			groupedKeys = append(groupedKeys, key)
+		}
+		groupedRows[key] = append(groupedRows[key], row)
+	}
+
+	gi.groupedRows = make([]rowContext, 0)
+	for _, key := range groupedKeys {
+		gi.groupedRows = append(gi.groupedRows, rowContext{
+			tables:       groupedRows[key][0].tables,
+			parameters:   groupedRows[key][0].parameters,
+			grouppedRows: groupedRows[key],
+		})
+	}
+
+	return gi.Next()
+}
+
+func (r rowContext) generateGroupByKey(groupBy []parsers.SelectItem) string {
+	var keyBuilder strings.Builder
+	for _, selectItem := range groupBy {
+		value := r.resolveSelectItem(selectItem)
+		keyBuilder.WriteString(fmt.Sprintf("%v", value))
+		keyBuilder.WriteString(":")
+	}
+	return keyBuilder.String()
+}

query_executors/memory_executor/join_iterator.go

@@ -0,0 +1,62 @@
+package memoryexecutor
+
+import (
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/parsers"
+)
+
+type joinIterator struct {
+	documents rowIterator
+	query     parsers.SelectStmt
+	buffer    []rowContext
+}
+
+func (ji *joinIterator) Next() (rowContext, datastore.DataStoreStatus) {
+	if ji.documents == nil {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	if len(ji.buffer) > 0 {
+		row := ji.buffer[0]
+		ji.buffer = ji.buffer[1:]
+		return row, datastore.StatusOk
+	}
+
+	doc, status := ji.documents.Next()
+	if status != datastore.StatusOk {
+		ji.documents = nil
+		return rowContext{}, status
+	}
+
+	ji.buffer = []rowContext{doc}
+	for _, joinItem := range ji.query.JoinItems {
+		nextDocuments := make([]rowContext, 0)
+		for _, row := range ji.buffer {
+			joinedItems := row.resolveJoinItemSelect(joinItem.SelectItem)
+			for _, joinedItem := range joinedItems {
+				tablesCopy := copyMap(row.tables)
+				tablesCopy[joinItem.Table.Value] = joinedItem
+				nextDocuments = append(nextDocuments, rowContext{
+					parameters: row.parameters,
+					tables:     tablesCopy,
+				})
+			}
+		}
+		ji.buffer = nextDocuments
+	}
+
+	return ji.Next()
+}
+
+func (r rowContext) resolveJoinItemSelect(selectItem parsers.SelectItem) []RowType {
+	if selectItem.Path != nil || selectItem.Type == parsers.SelectItemTypeSubQuery {
+		selectValue := r.parseArray(selectItem)
+		documents := make([]RowType, len(selectValue))
+		for i, newRowData := range selectValue {
+			documents[i] = newRowData
+		}
+		return documents
+	}
+
+	return []RowType{}
+}

query_executors/memory_executor/limit_iterator.go

@@ -0,0 +1,19 @@
+package memoryexecutor
+
+import "github.com/pikami/cosmium/internal/datastore"
+
+type limitIterator struct {
+	documents rowTypeIterator
+	limit     int
+	count     int
+}
+
+func (li *limitIterator) Next() (RowType, datastore.DataStoreStatus) {
+	if li.count >= li.limit {
+		li.documents = nil
+		return rowContext{}, datastore.IterEOF
+	}
+
+	li.count++
+	return li.documents.Next()
+}

query_executors/memory_executor/memory_executor.go

@@ -1,752 +1,92 @@
 package memoryexecutor
 
 import (
-	"fmt"
-	"reflect"
-	"sort"
-	"strconv"
-	"strings"
-
-	"github.com/pikami/cosmium/internal/logger"
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/parsers"
-	"golang.org/x/exp/slices"
 )
 
-type RowType interface{}
-type rowContext struct {
-	tables       map[string]RowType
-	parameters   map[string]interface{}
-	grouppedRows []rowContext
+func ExecuteQuery(query parsers.SelectStmt, documents rowTypeIterator) []RowType {
+	resultIter := executeQuery(query, &rowTypeToRowContextIterator{documents: documents, query: query})
+	result := make([]RowType, 0)
+	for {
+		row, status := resultIter.Next()
+		if status != datastore.StatusOk {
+			break
+		}
+
+		result = append(result, row)
+	}
+	return result
 }
 
-func ExecuteQuery(query parsers.SelectStmt, documents []RowType) []RowType {
-	currentDocuments := make([]rowContext, 0)
-	for _, doc := range documents {
-		currentDocuments = append(currentDocuments, resolveFrom(query, doc)...)
+func executeQuery(query parsers.SelectStmt, documents rowIterator) rowTypeIterator {
+	// Resolve FROM
+	var iter rowIterator = &fromIterator{
+		documents: documents,
+		table:     query.Table,
 	}
 
-	// Handle JOINS
-	nextDocuments := make([]rowContext, 0)
-	for _, currentDocument := range currentDocuments {
-		rowContexts := currentDocument.handleJoin(query)
-		nextDocuments = append(nextDocuments, rowContexts...)
-	}
-	currentDocuments = nextDocuments
-
-	// Apply filters
-	nextDocuments = make([]rowContext, 0)
-	for _, currentDocument := range currentDocuments {
-		if currentDocument.applyFilters(query.Filters) {
-			nextDocuments = append(nextDocuments, currentDocument)
+	// Apply JOIN
+	if len(query.JoinItems) > 0 {
+		iter = &joinIterator{
+			documents: iter,
+			query:     query,
 		}
 	}
-	currentDocuments = nextDocuments
 
-	// Apply order
+	// Apply WHERE
+	if query.Filters != nil {
+		iter = &filterIterator{
+			documents: iter,
+			filters:   query.Filters,
+		}
+	}
+
+	// Apply ORDER BY
 	if len(query.OrderExpressions) > 0 {
-		applyOrder(currentDocuments, query.OrderExpressions)
+		iter = &orderIterator{
+			documents:        iter,
+			orderExpressions: query.OrderExpressions,
+		}
 	}
 
-	// Apply group by
+	// Apply GROUP BY
 	if len(query.GroupBy) > 0 {
-		currentDocuments = applyGroupBy(currentDocuments, query.GroupBy)
+		iter = &groupByIterator{
+			documents: iter,
+			groupBy:   query.GroupBy,
+		}
 	}
 
-	// Apply select
-	projectedDocuments := applyProjection(currentDocuments, query.SelectItems, query.GroupBy)
+	// Apply SELECT
+	var projectedIterator rowTypeIterator = &projectIterator{
+		documents:   iter,
+		selectItems: query.SelectItems,
+		groupBy:     query.GroupBy,
+	}
 
-	// Apply distinct
+	// Apply DISTINCT
 	if query.Distinct {
-		projectedDocuments = deduplicate(projectedDocuments)
+		projectedIterator = &distinctIterator{
+			documents: projectedIterator,
+		}
 	}
 
-	// Apply offset
+	// Apply OFFSET
 	if query.Offset > 0 {
-		if query.Offset < len(projectedDocuments) {
-			projectedDocuments = projectedDocuments[query.Offset:]
-		} else {
-			projectedDocuments = []RowType{}
+		projectedIterator = &offsetIterator{
+			documents: projectedIterator,
+			offset:    query.Offset,
 		}
 	}
 
-	// Apply result limit
-	if query.Count > 0 && len(projectedDocuments) > query.Count {
-		projectedDocuments = projectedDocuments[:query.Count]
+	// Apply LIMIT
+	if query.Count > 0 {
+		projectedIterator = &limitIterator{
+			documents: projectedIterator,
+			limit:     query.Count,
+		}
 	}
 
-	return projectedDocuments
-}
-
-func resolveFrom(query parsers.SelectStmt, doc RowType) []rowContext {
-	initialRow, gotParentContext := doc.(rowContext)
-	if !gotParentContext {
-		var initialTableName string
-		if query.Table.SelectItem.Type == parsers.SelectItemTypeSubQuery {
-			initialTableName = query.Table.SelectItem.Value.(parsers.SelectStmt).Table.Value
-		}
-
-		if initialTableName == "" {
-			initialTableName = query.Table.Value
-		}
-
-		if initialTableName == "" {
-			initialTableName = resolveDestinationColumnName(query.Table.SelectItem, 0, query.Parameters)
-		}
-
-		initialRow = rowContext{
-			parameters: query.Parameters,
-			tables: map[string]RowType{
-				initialTableName: doc,
-				"$root":          doc,
-			},
-		}
-	}
-
-	if query.Table.SelectItem.Path != nil || query.Table.SelectItem.Type == parsers.SelectItemTypeSubQuery {
-		destinationTableName := query.Table.SelectItem.Alias
-		if destinationTableName == "" {
-			destinationTableName = query.Table.Value
-		}
-		if destinationTableName == "" {
-			destinationTableName = resolveDestinationColumnName(query.Table.SelectItem, 0, initialRow.parameters)
-		}
-
-		if query.Table.IsInSelect || query.Table.SelectItem.Type == parsers.SelectItemTypeSubQuery {
-			selectValue := initialRow.parseArray(query.Table.SelectItem)
-			rowContexts := make([]rowContext, len(selectValue))
-			for i, newRowData := range selectValue {
-				rowContexts[i].parameters = initialRow.parameters
-				rowContexts[i].tables = copyMap(initialRow.tables)
-				rowContexts[i].tables[destinationTableName] = newRowData
-			}
-			return rowContexts
-		}
-
-		if len(query.Table.SelectItem.Path) > 0 {
-			sourceTableName := query.Table.SelectItem.Path[0]
-			sourceTableData := initialRow.tables[sourceTableName]
-			if sourceTableData == nil {
-				// When source table is not found, assume it's root document
-				initialRow.tables[sourceTableName] = initialRow.tables["$root"]
-			}
-		}
-
-		newRowData := initialRow.resolveSelectItem(query.Table.SelectItem)
-		initialRow.tables[destinationTableName] = newRowData
-		return []rowContext{initialRow}
-	}
-
-	return []rowContext{initialRow}
-}
-
-func (r rowContext) handleJoin(query parsers.SelectStmt) []rowContext {
-	currentDocuments := []rowContext{r}
-
-	for _, joinItem := range query.JoinItems {
-		nextDocuments := make([]rowContext, 0)
-		for _, currentDocument := range currentDocuments {
-			joinedItems := currentDocument.resolveJoinItemSelect(joinItem.SelectItem)
-			for _, joinedItem := range joinedItems {
-				tablesCopy := copyMap(currentDocument.tables)
-				tablesCopy[joinItem.Table.Value] = joinedItem
-				nextDocuments = append(nextDocuments, rowContext{
-					parameters: currentDocument.parameters,
-					tables:     tablesCopy,
-				})
-			}
-		}
-		currentDocuments = nextDocuments
-	}
-
-	return currentDocuments
-}
-
-func (r rowContext) resolveJoinItemSelect(selectItem parsers.SelectItem) []RowType {
-	if selectItem.Path != nil || selectItem.Type == parsers.SelectItemTypeSubQuery {
-		selectValue := r.parseArray(selectItem)
-		documents := make([]RowType, len(selectValue))
-		for i, newRowData := range selectValue {
-			documents[i] = newRowData
-		}
-		return documents
-	}
-
-	return []RowType{}
-}
-
-func (r rowContext) applyFilters(filters interface{}) bool {
-	if filters == nil {
-		return true
-	}
-
-	switch typedFilters := filters.(type) {
-	case parsers.ComparisonExpression:
-		return r.filters_ComparisonExpression(typedFilters)
-	case parsers.LogicalExpression:
-		return r.filters_LogicalExpression(typedFilters)
-	case parsers.Constant:
-		if value, ok := typedFilters.Value.(bool); ok {
-			return value
-		}
-		return false
-	case parsers.SelectItem:
-		resolvedValue := r.resolveSelectItem(typedFilters)
-		if value, ok := resolvedValue.(bool); ok {
-			if typedFilters.Invert {
-				return !value
-			}
-
-			return value
-		}
-	}
-
-	return false
-}
-
-func (r rowContext) filters_ComparisonExpression(expression parsers.ComparisonExpression) bool {
-	leftExpression, leftExpressionOk := expression.Left.(parsers.SelectItem)
-	rightExpression, rightExpressionOk := expression.Right.(parsers.SelectItem)
-
-	if !leftExpressionOk || !rightExpressionOk {
-		logger.ErrorLn("ComparisonExpression has incorrect Left or Right type")
-		return false
-	}
-
-	leftValue := r.resolveSelectItem(leftExpression)
-	rightValue := r.resolveSelectItem(rightExpression)
-
-	cmp := compareValues(leftValue, rightValue)
-	switch expression.Operation {
-	case "=":
-		return cmp == 0
-	case "!=":
-		return cmp != 0
-	case "<":
-		return cmp < 0
-	case ">":
-		return cmp > 0
-	case "<=":
-		return cmp <= 0
-	case ">=":
-		return cmp >= 0
-	}
-
-	return false
-}
-
-func (r rowContext) filters_LogicalExpression(expression parsers.LogicalExpression) bool {
-	var result bool
-	for i, subExpression := range expression.Expressions {
-		expressionResult := r.applyFilters(subExpression)
-		if i == 0 {
-			result = expressionResult
-		}
-
-		switch expression.Operation {
-		case parsers.LogicalExpressionTypeAnd:
-			result = result && expressionResult
-			if !result {
-				return false
-			}
-		case parsers.LogicalExpressionTypeOr:
-			result = result || expressionResult
-			if result {
-				return true
-			}
-		}
-	}
-	return result
-}
-
-func applyOrder(documents []rowContext, orderExpressions []parsers.OrderExpression) {
-	less := func(i, j int) bool {
-		for _, order := range orderExpressions {
-			val1 := documents[i].resolveSelectItem(order.SelectItem)
-			val2 := documents[j].resolveSelectItem(order.SelectItem)
-
-			cmp := compareValues(val1, val2)
-			if cmp != 0 {
-				if order.Direction == parsers.OrderDirectionDesc {
-					return cmp > 0
-				}
-				return cmp < 0
-			}
-		}
-		return i < j
-	}
-
-	sort.SliceStable(documents, less)
-}
-
-func applyGroupBy(documents []rowContext, groupBy []parsers.SelectItem) []rowContext {
-	groupedRows := make(map[string][]rowContext)
-	groupedKeys := make([]string, 0)
-
-	for _, row := range documents {
-		key := row.generateGroupByKey(groupBy)
-		if _, ok := groupedRows[key]; !ok {
-			groupedKeys = append(groupedKeys, key)
-		}
-		groupedRows[key] = append(groupedRows[key], row)
-	}
-
-	grouppedRows := make([]rowContext, 0)
-	for _, key := range groupedKeys {
-		grouppedRowContext := rowContext{
-			tables:       groupedRows[key][0].tables,
-			parameters:   groupedRows[key][0].parameters,
-			grouppedRows: groupedRows[key],
-		}
-		grouppedRows = append(grouppedRows, grouppedRowContext)
-	}
-
-	return grouppedRows
-}
-
-func (r rowContext) generateGroupByKey(groupBy []parsers.SelectItem) string {
-	var keyBuilder strings.Builder
-	for _, selectItem := range groupBy {
-		value := r.resolveSelectItem(selectItem)
-		keyBuilder.WriteString(fmt.Sprintf("%v", value))
-		keyBuilder.WriteString(":")
-	}
-	return keyBuilder.String()
-}
-
-func applyProjection(documents []rowContext, selectItems []parsers.SelectItem, groupBy []parsers.SelectItem) []RowType {
-	if len(documents) == 0 {
-		return []RowType{}
-	}
-
-	if hasAggregateFunctions(selectItems) && len(groupBy) == 0 {
-		// When can have aggregate functions without GROUP BY clause,
-		// we should aggregate all rows in that case
-		rowContext := rowContext{
-			tables:       documents[0].tables,
-			parameters:   documents[0].parameters,
-			grouppedRows: documents,
-		}
-		return []RowType{rowContext.applyProjection(selectItems)}
-	}
-
-	projectedDocuments := make([]RowType, len(documents))
-	for index, row := range documents {
-		projectedDocuments[index] = row.applyProjection(selectItems)
-	}
-
-	return projectedDocuments
-}
-
-func (r rowContext) applyProjection(selectItems []parsers.SelectItem) RowType {
-	// When the first value is top level, select it instead
-	if len(selectItems) > 0 && selectItems[0].IsTopLevel {
-		return r.resolveSelectItem(selectItems[0])
-	}
-
-	// Construct a new row based on the selected columns
-	row := make(map[string]interface{})
-	for index, selectItem := range selectItems {
-		destinationName := resolveDestinationColumnName(selectItem, index, r.parameters)
-
-		row[destinationName] = r.resolveSelectItem(selectItem)
-	}
-
-	return row
-}
-
-func resolveDestinationColumnName(selectItem parsers.SelectItem, itemIndex int, queryParameters map[string]interface{}) string {
-	if selectItem.Alias != "" {
-		return selectItem.Alias
-	}
-
-	destinationName := fmt.Sprintf("$%d", itemIndex+1)
-	if len(selectItem.Path) > 0 {
-		destinationName = selectItem.Path[len(selectItem.Path)-1]
-	}
-
-	if destinationName[0] == '@' {
-		destinationName = queryParameters[destinationName].(string)
-	}
-
-	return destinationName
-}
-
-func (r rowContext) resolveSelectItem(selectItem parsers.SelectItem) interface{} {
-	if selectItem.Type == parsers.SelectItemTypeArray {
-		return r.selectItem_SelectItemTypeArray(selectItem)
-	}
-
-	if selectItem.Type == parsers.SelectItemTypeObject {
-		return r.selectItem_SelectItemTypeObject(selectItem)
-	}
-
-	if selectItem.Type == parsers.SelectItemTypeConstant {
-		return r.selectItem_SelectItemTypeConstant(selectItem)
-	}
-
-	if selectItem.Type == parsers.SelectItemTypeSubQuery {
-		return r.selectItem_SelectItemTypeSubQuery(selectItem)
-	}
-
-	if selectItem.Type == parsers.SelectItemTypeFunctionCall {
-		if typedFunctionCall, ok := selectItem.Value.(parsers.FunctionCall); ok {
-			return r.selectItem_SelectItemTypeFunctionCall(typedFunctionCall)
-		}
-
-		logger.ErrorLn("parsers.SelectItem has incorrect Value type (expected parsers.FunctionCall)")
-		return nil
-	}
-
-	return r.selectItem_SelectItemTypeField(selectItem)
-}
-
-func (r rowContext) selectItem_SelectItemTypeArray(selectItem parsers.SelectItem) interface{} {
-	arrayValue := make([]interface{}, 0)
-	for _, subSelectItem := range selectItem.SelectItems {
-		arrayValue = append(arrayValue, r.resolveSelectItem(subSelectItem))
-	}
-	return arrayValue
-}
-
-func (r rowContext) selectItem_SelectItemTypeObject(selectItem parsers.SelectItem) interface{} {
-	objectValue := make(map[string]interface{})
-	for _, subSelectItem := range selectItem.SelectItems {
-		objectValue[subSelectItem.Alias] = r.resolveSelectItem(subSelectItem)
-	}
-	return objectValue
-}
-
-func (r rowContext) selectItem_SelectItemTypeConstant(selectItem parsers.SelectItem) interface{} {
-	var typedValue parsers.Constant
-	var ok bool
-	if typedValue, ok = selectItem.Value.(parsers.Constant); !ok {
-		// TODO: Handle error
-		logger.ErrorLn("parsers.Constant has incorrect Value type")
-	}
-
-	if typedValue.Type == parsers.ConstantTypeParameterConstant &&
-		r.parameters != nil {
-		if key, ok := typedValue.Value.(string); ok {
-			return r.parameters[key]
-		}
-	}
-
-	return typedValue.Value
-}
-
-func (r rowContext) selectItem_SelectItemTypeSubQuery(selectItem parsers.SelectItem) interface{} {
-	subQuery := selectItem.Value.(parsers.SelectStmt)
-	subQueryResult := ExecuteQuery(
-		subQuery,
-		[]RowType{r},
-	)
-
-	if subQuery.Exists {
-		return len(subQueryResult) > 0
-	}
-
-	return subQueryResult
-}
-
-func (r rowContext) selectItem_SelectItemTypeFunctionCall(functionCall parsers.FunctionCall) interface{} {
-	switch functionCall.Type {
-	case parsers.FunctionCallStringEquals:
-		return r.strings_StringEquals(functionCall.Arguments)
-	case parsers.FunctionCallContains:
-		return r.strings_Contains(functionCall.Arguments)
-	case parsers.FunctionCallEndsWith:
-		return r.strings_EndsWith(functionCall.Arguments)
-	case parsers.FunctionCallStartsWith:
-		return r.strings_StartsWith(functionCall.Arguments)
-	case parsers.FunctionCallConcat:
-		return r.strings_Concat(functionCall.Arguments)
-	case parsers.FunctionCallIndexOf:
-		return r.strings_IndexOf(functionCall.Arguments)
-	case parsers.FunctionCallToString:
-		return r.strings_ToString(functionCall.Arguments)
-	case parsers.FunctionCallUpper:
-		return r.strings_Upper(functionCall.Arguments)
-	case parsers.FunctionCallLower:
-		return r.strings_Lower(functionCall.Arguments)
-	case parsers.FunctionCallLeft:
-		return r.strings_Left(functionCall.Arguments)
-	case parsers.FunctionCallLength:
-		return r.strings_Length(functionCall.Arguments)
-	case parsers.FunctionCallLTrim:
-		return r.strings_LTrim(functionCall.Arguments)
-	case parsers.FunctionCallReplace:
-		return r.strings_Replace(functionCall.Arguments)
-	case parsers.FunctionCallReplicate:
-		return r.strings_Replicate(functionCall.Arguments)
-	case parsers.FunctionCallReverse:
-		return r.strings_Reverse(functionCall.Arguments)
-	case parsers.FunctionCallRight:
-		return r.strings_Right(functionCall.Arguments)
-	case parsers.FunctionCallRTrim:
-		return r.strings_RTrim(functionCall.Arguments)
-	case parsers.FunctionCallSubstring:
-		return r.strings_Substring(functionCall.Arguments)
-	case parsers.FunctionCallTrim:
-		return r.strings_Trim(functionCall.Arguments)
-
-	case parsers.FunctionCallIsDefined:
-		return r.typeChecking_IsDefined(functionCall.Arguments)
-	case parsers.FunctionCallIsArray:
-		return r.typeChecking_IsArray(functionCall.Arguments)
-	case parsers.FunctionCallIsBool:
-		return r.typeChecking_IsBool(functionCall.Arguments)
-	case parsers.FunctionCallIsFiniteNumber:
-		return r.typeChecking_IsFiniteNumber(functionCall.Arguments)
-	case parsers.FunctionCallIsInteger:
-		return r.typeChecking_IsInteger(functionCall.Arguments)
-	case parsers.FunctionCallIsNull:
-		return r.typeChecking_IsNull(functionCall.Arguments)
-	case parsers.FunctionCallIsNumber:
-		return r.typeChecking_IsNumber(functionCall.Arguments)
-	case parsers.FunctionCallIsObject:
-		return r.typeChecking_IsObject(functionCall.Arguments)
-	case parsers.FunctionCallIsPrimitive:
-		return r.typeChecking_IsPrimitive(functionCall.Arguments)
-	case parsers.FunctionCallIsString:
-		return r.typeChecking_IsString(functionCall.Arguments)
-
-	case parsers.FunctionCallArrayConcat:
-		return r.array_Concat(functionCall.Arguments)
-	case parsers.FunctionCallArrayContains:
-		return r.array_Contains(functionCall.Arguments)
-	case parsers.FunctionCallArrayContainsAny:
-		return r.array_Contains_Any(functionCall.Arguments)
-	case parsers.FunctionCallArrayContainsAll:
-		return r.array_Contains_All(functionCall.Arguments)
-	case parsers.FunctionCallArrayLength:
-		return r.array_Length(functionCall.Arguments)
-	case parsers.FunctionCallArraySlice:
-		return r.array_Slice(functionCall.Arguments)
-	case parsers.FunctionCallSetIntersect:
-		return r.set_Intersect(functionCall.Arguments)
-	case parsers.FunctionCallSetUnion:
-		return r.set_Union(functionCall.Arguments)
-
-	case parsers.FunctionCallMathAbs:
-		return r.math_Abs(functionCall.Arguments)
-	case parsers.FunctionCallMathAcos:
-		return r.math_Acos(functionCall.Arguments)
-	case parsers.FunctionCallMathAsin:
-		return r.math_Asin(functionCall.Arguments)
-	case parsers.FunctionCallMathAtan:
-		return r.math_Atan(functionCall.Arguments)
-	case parsers.FunctionCallMathCeiling:
-		return r.math_Ceiling(functionCall.Arguments)
-	case parsers.FunctionCallMathCos:
-		return r.math_Cos(functionCall.Arguments)
-	case parsers.FunctionCallMathCot:
-		return r.math_Cot(functionCall.Arguments)
-	case parsers.FunctionCallMathDegrees:
-		return r.math_Degrees(functionCall.Arguments)
-	case parsers.FunctionCallMathExp:
-		return r.math_Exp(functionCall.Arguments)
-	case parsers.FunctionCallMathFloor:
-		return r.math_Floor(functionCall.Arguments)
-	case parsers.FunctionCallMathIntBitNot:
-		return r.math_IntBitNot(functionCall.Arguments)
-	case parsers.FunctionCallMathLog10:
-		return r.math_Log10(functionCall.Arguments)
-	case parsers.FunctionCallMathRadians:
-		return r.math_Radians(functionCall.Arguments)
-	case parsers.FunctionCallMathRound:
-		return r.math_Round(functionCall.Arguments)
-	case parsers.FunctionCallMathSign:
-		return r.math_Sign(functionCall.Arguments)
-	case parsers.FunctionCallMathSin:
-		return r.math_Sin(functionCall.Arguments)
-	case parsers.FunctionCallMathSqrt:
-		return r.math_Sqrt(functionCall.Arguments)
-	case parsers.FunctionCallMathSquare:
-		return r.math_Square(functionCall.Arguments)
-	case parsers.FunctionCallMathTan:
-		return r.math_Tan(functionCall.Arguments)
-	case parsers.FunctionCallMathTrunc:
-		return r.math_Trunc(functionCall.Arguments)
-	case parsers.FunctionCallMathAtn2:
-		return r.math_Atn2(functionCall.Arguments)
-	case parsers.FunctionCallMathIntAdd:
-		return r.math_IntAdd(functionCall.Arguments)
-	case parsers.FunctionCallMathIntBitAnd:
-		return r.math_IntBitAnd(functionCall.Arguments)
-	case parsers.FunctionCallMathIntBitLeftShift:
-		return r.math_IntBitLeftShift(functionCall.Arguments)
-	case parsers.FunctionCallMathIntBitOr:
-		return r.math_IntBitOr(functionCall.Arguments)
-	case parsers.FunctionCallMathIntBitRightShift:
-		return r.math_IntBitRightShift(functionCall.Arguments)
-	case parsers.FunctionCallMathIntBitXor:
-		return r.math_IntBitXor(functionCall.Arguments)
-	case parsers.FunctionCallMathIntDiv:
-		return r.math_IntDiv(functionCall.Arguments)
-	case parsers.FunctionCallMathIntMod:
-		return r.math_IntMod(functionCall.Arguments)
-	case parsers.FunctionCallMathIntMul:
-		return r.math_IntMul(functionCall.Arguments)
-	case parsers.FunctionCallMathIntSub:
-		return r.math_IntSub(functionCall.Arguments)
-	case parsers.FunctionCallMathPower:
-		return r.math_Power(functionCall.Arguments)
-	case parsers.FunctionCallMathLog:
-		return r.math_Log(functionCall.Arguments)
-	case parsers.FunctionCallMathNumberBin:
-		return r.math_NumberBin(functionCall.Arguments)
-	case parsers.FunctionCallMathPi:
-		return r.math_Pi()
-	case parsers.FunctionCallMathRand:
-		return r.math_Rand()
-
-	case parsers.FunctionCallAggregateAvg:
-		return r.aggregate_Avg(functionCall.Arguments)
-	case parsers.FunctionCallAggregateCount:
-		return r.aggregate_Count(functionCall.Arguments)
-	case parsers.FunctionCallAggregateMax:
-		return r.aggregate_Max(functionCall.Arguments)
-	case parsers.FunctionCallAggregateMin:
-		return r.aggregate_Min(functionCall.Arguments)
-	case parsers.FunctionCallAggregateSum:
-		return r.aggregate_Sum(functionCall.Arguments)
-
-	case parsers.FunctionCallIn:
-		return r.misc_In(functionCall.Arguments)
-	}
-
-	logger.Errorf("Unknown function call type: %v", functionCall.Type)
-	return nil
-}
-
-func (r rowContext) selectItem_SelectItemTypeField(selectItem parsers.SelectItem) interface{} {
-	value := r.tables[selectItem.Path[0]]
-
-	if len(selectItem.Path) > 1 {
-		for _, pathSegment := range selectItem.Path[1:] {
-			if pathSegment[0] == '@' {
-				pathSegment = r.parameters[pathSegment].(string)
-			}
-
-			switch nestedValue := value.(type) {
-			case map[string]interface{}:
-				value = nestedValue[pathSegment]
-			case map[string]RowType:
-				value = nestedValue[pathSegment]
-			case []int, []string, []interface{}:
-				slice := reflect.ValueOf(nestedValue)
-				if arrayIndex, err := strconv.Atoi(pathSegment); err == nil && slice.Len() > arrayIndex {
-					value = slice.Index(arrayIndex).Interface()
-				} else {
-					return nil
-				}
-			default:
-				return nil
-			}
-		}
-	}
-
-	return value
-}
-
-func hasAggregateFunctions(selectItems []parsers.SelectItem) bool {
-	if selectItems == nil {
-		return false
-	}
-
-	for _, selectItem := range selectItems {
-		if selectItem.Type == parsers.SelectItemTypeFunctionCall {
-			if typedValue, ok := selectItem.Value.(parsers.FunctionCall); ok && slices.Contains[[]parsers.FunctionCallType](parsers.AggregateFunctions, typedValue.Type) {
-				return true
-			}
-		}
-
-		if hasAggregateFunctions(selectItem.SelectItems) {
-			return true
-		}
-	}
-
-	return false
-}
-
-func compareValues(val1, val2 interface{}) int {
-	if val1 == nil && val2 == nil {
-		return 0
-	} else if val1 == nil {
-		return -1
-	} else if val2 == nil {
-		return 1
-	}
-
-	if reflect.TypeOf(val1) != reflect.TypeOf(val2) {
-		return 1
-	}
-
-	switch val1 := val1.(type) {
-	case int:
-		val2 := val2.(int)
-		if val1 < val2 {
-			return -1
-		} else if val1 > val2 {
-			return 1
-		}
-		return 0
-	case float64:
-		val2 := val2.(float64)
-		if val1 < val2 {
-			return -1
-		} else if val1 > val2 {
-			return 1
-		}
-		return 0
-	case string:
-		val2 := val2.(string)
-		return strings.Compare(val1, val2)
-	case bool:
-		val2 := val2.(bool)
-		if val1 == val2 {
-			return 0
-		} else if val1 {
-			return 1
-		} else {
-			return -1
-		}
-	// TODO: Add more types
-	default:
-		if reflect.DeepEqual(val1, val2) {
-			return 0
-		}
-		return 1
-	}
-}
-
-func deduplicate[T RowType | interface{}](slice []T) []T {
-	var result []T
-	result = make([]T, 0)
-
-	for i := 0; i < len(slice); i++ {
-		unique := true
-		for j := 0; j < len(result); j++ {
-			if compareValues(slice[i], result[j]) == 0 {
-				unique = false
-				break
-			}
-		}
-
-		if unique {
-			result = append(result, slice[i])
-		}
-	}
-
-	return result
-}
-
-func copyMap[T RowType | []RowType](originalMap map[string]T) map[string]T {
-	targetMap := make(map[string]T)
-
-	for k, v := range originalMap {
-		targetMap[k] = v
-	}
-
-	return targetMap
+	return projectedIterator
 }

query_executors/memory_executor/misc_test.go

@@ -4,18 +4,41 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/pikami/cosmium/internal/datastore"
 	"github.com/pikami/cosmium/parsers"
 	memoryexecutor "github.com/pikami/cosmium/query_executors/memory_executor"
 	testutils "github.com/pikami/cosmium/test_utils"
 )
 
+type TestDocumentIterator struct {
+	documents []memoryexecutor.RowType
+	index     int
+}
+
+func NewTestDocumentIterator(documents []memoryexecutor.RowType) *TestDocumentIterator {
+	return &TestDocumentIterator{
+		documents: documents,
+		index:     -1,
+	}
+}
+
+func (i *TestDocumentIterator) Next() (memoryexecutor.RowType, datastore.DataStoreStatus) {
+	i.index++
+	if i.index >= len(i.documents) {
+		return nil, datastore.IterEOF
+	}
+
+	return i.documents[i.index], datastore.StatusOk
+}
+
 func testQueryExecute(
 	t *testing.T,
 	query parsers.SelectStmt,
 	data []memoryexecutor.RowType,
 	expectedData []memoryexecutor.RowType,
 ) {
-	result := memoryexecutor.ExecuteQuery(query, data)
+	iter := NewTestDocumentIterator(data)
+	result := memoryexecutor.ExecuteQuery(query, iter)
 
 	if !reflect.DeepEqual(result, expectedData) {
 		t.Errorf("execution result does not match expected data.\nExpected: %+v\nGot: %+v", expectedData, result)

query_executors/memory_executor/offset_iterator.go

@@ -0,0 +1,22 @@
+package memoryexecutor
+
+import "github.com/pikami/cosmium/internal/datastore"
+
+type offsetIterator struct {
+	documents rowTypeIterator
+	offset    int
+	skipped   bool
+}
+
+func (oi *offsetIterator) Next() (RowType, datastore.DataStoreStatus) {
+	if oi.skipped {
+		return oi.documents.Next()
+	}
+
+	for i := 0; i < oi.offset; i++ {
+		oi.documents.Next()
+	}
+
+	oi.skipped = true
+	return oi.Next()
+}

query_executors/memory_executor/order_iterator.go

@@ -0,0 +1,63 @@
+package memoryexecutor
+
+import (
+	"sort"
+
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/parsers"
+)
+
+type orderIterator struct {
+	documents        rowIterator
+	orderExpressions []parsers.OrderExpression
+	orderedDocs      []rowContext
+	docsIndex        int
+}
+
+func (oi *orderIterator) Next() (rowContext, datastore.DataStoreStatus) {
+	if oi.orderedDocs != nil {
+		if oi.docsIndex >= len(oi.orderedDocs) {
+			return rowContext{}, datastore.IterEOF
+		}
+		row := oi.orderedDocs[oi.docsIndex]
+		oi.orderedDocs[oi.docsIndex] = rowContext{}
+		oi.docsIndex++
+		return row, datastore.StatusOk
+	}
+
+	oi.orderedDocs = make([]rowContext, 0)
+	for {
+		row, status := oi.documents.Next()
+		if status != datastore.StatusOk {
+			break
+		}
+
+		oi.orderedDocs = append(oi.orderedDocs, row)
+	}
+	oi.documents = nil
+
+	less := func(i, j int) bool {
+		for _, order := range oi.orderExpressions {
+			val1 := oi.orderedDocs[i].resolveSelectItem(order.SelectItem)
+			val2 := oi.orderedDocs[j].resolveSelectItem(order.SelectItem)
+
+			cmp := compareValues(val1, val2)
+			if cmp != 0 {
+				if order.Direction == parsers.OrderDirectionDesc {
+					return cmp > 0
+				}
+				return cmp < 0
+			}
+		}
+		return i < j
+	}
+
+	sort.SliceStable(oi.orderedDocs, less)
+
+	if len(oi.orderedDocs) == 0 {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	oi.docsIndex = 1
+	return oi.orderedDocs[0], datastore.StatusOk
+}

query_executors/memory_executor/project_iterator.go

@@ -0,0 +1,90 @@
+package memoryexecutor
+
+import (
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/parsers"
+	"golang.org/x/exp/slices"
+)
+
+type projectIterator struct {
+	documents   rowIterator
+	selectItems []parsers.SelectItem
+	groupBy     []parsers.SelectItem
+}
+
+func (pi *projectIterator) Next() (RowType, datastore.DataStoreStatus) {
+	if pi.documents == nil {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	row, status := pi.documents.Next()
+	if status != datastore.StatusOk {
+		pi.documents = nil
+		return rowContext{}, status
+	}
+
+	if hasAggregateFunctions(pi.selectItems) && len(pi.groupBy) == 0 {
+		// When can have aggregate functions without GROUP BY clause,
+		// we should aggregate all rows in that case.
+		allDocuments := []rowContext{row}
+		for {
+			row, status := pi.documents.Next()
+			if status != datastore.StatusOk {
+				break
+			}
+
+			allDocuments = append(allDocuments, row)
+		}
+
+		if len(allDocuments) == 0 {
+			return rowContext{}, datastore.IterEOF
+		}
+
+		aggRow := rowContext{
+			tables:       row.tables,
+			parameters:   row.parameters,
+			grouppedRows: allDocuments,
+		}
+
+		return aggRow.applyProjection(pi.selectItems), datastore.StatusOk
+	}
+
+	return row.applyProjection(pi.selectItems), datastore.StatusOk
+}
+
+func (r rowContext) applyProjection(selectItems []parsers.SelectItem) RowType {
+	// When the first value is top level, select it instead
+	if len(selectItems) > 0 && selectItems[0].IsTopLevel {
+		return r.resolveSelectItem(selectItems[0])
+	}
+
+	// Construct a new row based on the selected columns
+	row := make(map[string]interface{})
+	for index, selectItem := range selectItems {
+		destinationName := resolveDestinationColumnName(selectItem, index, r.parameters)
+
+		row[destinationName] = r.resolveSelectItem(selectItem)
+	}
+
+	return row
+}
+
+func hasAggregateFunctions(selectItems []parsers.SelectItem) bool {
+	if selectItems == nil {
+		return false
+	}
+
+	for _, selectItem := range selectItems {
+		if selectItem.Type == parsers.SelectItemTypeFunctionCall {
+			if typedValue, ok := selectItem.Value.(parsers.FunctionCall); ok && slices.Contains[[]parsers.FunctionCallType](parsers.AggregateFunctions, typedValue.Type) {
+				return true
+			}
+		}
+
+		if hasAggregateFunctions(selectItem.SelectItems) {
+			return true
+		}
+	}
+
+	return false
+}

query_executors/memory_executor/rowTypeToRowContext_iterator.go

@@ -0,0 +1,44 @@
+package memoryexecutor
+
+import (
+	"github.com/pikami/cosmium/internal/datastore"
+	"github.com/pikami/cosmium/parsers"
+)
+
+type rowTypeToRowContextIterator struct {
+	documents rowTypeIterator
+	query     parsers.SelectStmt
+}
+
+func (di *rowTypeToRowContextIterator) Next() (rowContext, datastore.DataStoreStatus) {
+	if di.documents == nil {
+		return rowContext{}, datastore.IterEOF
+	}
+
+	doc, status := di.documents.Next()
+	if status != datastore.StatusOk {
+		di.documents = nil
+		return rowContext{}, status
+	}
+
+	var initialTableName string
+	if di.query.Table.SelectItem.Type == parsers.SelectItemTypeSubQuery {
+		initialTableName = di.query.Table.SelectItem.Value.(parsers.SelectStmt).Table.Value
+	}
+
+	if initialTableName == "" {
+		initialTableName = di.query.Table.Value
+	}
+
+	if initialTableName == "" {
+		initialTableName = resolveDestinationColumnName(di.query.Table.SelectItem, 0, di.query.Parameters)
+	}
+
+	return rowContext{
+		parameters: di.query.Parameters,
+		tables: map[string]RowType{
+			initialTableName: doc,
+			"$root":          doc,
+		},
+	}, status
+}

sharedlibrary/collections.go

@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 	"strings"
 
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 //export CreateCollection
@@ -20,15 +20,15 @@ func CreateCollection(serverName *C.char, databaseId *C.char, collectionJson *C.
 		return ResponseServerInstanceNotFound
 	}
 
-	var collection repositorymodels.Collection
+	var collection datastore.Collection
 	err := json.NewDecoder(strings.NewReader(collectionStr)).Decode(&collection)
 	if err != nil {
 		return ResponseFailedToParseRequest
 	}
 
-	_, code := serverInstance.repository.CreateCollection(databaseIdStr, collection)
+	_, code := serverInstance.dataStore.CreateCollection(databaseIdStr, collection)
 
-	return repositoryStatusToResponseCode(code)
+	return dataStoreStatusToResponseCode(code)
 }
 
 //export GetCollection
@@ -43,8 +43,8 @@ func GetCollection(serverName *C.char, databaseId *C.char, collectionId *C.char)
 		return C.CString("")
 	}
 
-	collection, code := serverInstance.repository.GetCollection(databaseIdStr, collectionIdStr)
-	if code != repositorymodels.StatusOk {
+	collection, code := serverInstance.dataStore.GetCollection(databaseIdStr, collectionIdStr)
+	if code != datastore.StatusOk {
 		return C.CString("")
 	}
 
@@ -66,8 +66,8 @@ func GetAllCollections(serverName *C.char, databaseId *C.char) *C.char {
 		return C.CString("")
 	}
 
-	collections, code := serverInstance.repository.GetAllCollections(databaseIdStr)
-	if code != repositorymodels.StatusOk {
+	collections, code := serverInstance.dataStore.GetAllCollections(databaseIdStr)
+	if code != datastore.StatusOk {
 		return C.CString("")
 	}
 
@@ -90,7 +90,7 @@ func DeleteCollection(serverName *C.char, databaseId *C.char, collectionId *C.ch
 		return ResponseServerInstanceNotFound
 	}
 
-	code := serverInstance.repository.DeleteCollection(databaseIdStr, collectionIdStr)
+	code := serverInstance.dataStore.DeleteCollection(databaseIdStr, collectionIdStr)
 
-	return repositoryStatusToResponseCode(code)
+	return dataStoreStatusToResponseCode(code)
 }

sharedlibrary/databases.go

@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 	"strings"
 
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 //export CreateDatabase
@@ -19,15 +19,15 @@ func CreateDatabase(serverName *C.char, databaseJson *C.char) int {
 		return ResponseServerInstanceNotFound
 	}
 
-	var database repositorymodels.Database
+	var database datastore.Database
 	err := json.NewDecoder(strings.NewReader(databaseStr)).Decode(&database)
 	if err != nil {
 		return ResponseFailedToParseRequest
 	}
 
-	_, code := serverInstance.repository.CreateDatabase(database)
+	_, code := serverInstance.dataStore.CreateDatabase(database)
 
-	return repositoryStatusToResponseCode(code)
+	return dataStoreStatusToResponseCode(code)
 }
 
 //export GetDatabase
@@ -41,8 +41,8 @@ func GetDatabase(serverName *C.char, databaseId *C.char) *C.char {
 		return C.CString("")
 	}
 
-	database, code := serverInstance.repository.GetDatabase(databaseIdStr)
-	if code != repositorymodels.StatusOk {
+	database, code := serverInstance.dataStore.GetDatabase(databaseIdStr)
+	if code != datastore.StatusOk {
 		return C.CString("")
 	}
 
@@ -63,8 +63,8 @@ func GetAllDatabases(serverName *C.char) *C.char {
 		return C.CString("")
 	}
 
-	databases, code := serverInstance.repository.GetAllDatabases()
-	if code != repositorymodels.StatusOk {
+	databases, code := serverInstance.dataStore.GetAllDatabases()
+	if code != datastore.StatusOk {
 		return C.CString("")
 	}
 
@@ -87,7 +87,7 @@ func DeleteDatabase(serverName *C.char, databaseId *C.char) int {
 		return ResponseServerInstanceNotFound
 	}
 
-	code := serverInstance.repository.DeleteDatabase(databaseIdStr)
+	code := serverInstance.dataStore.DeleteDatabase(databaseIdStr)
 
-	return repositoryStatusToResponseCode(code)
+	return dataStoreStatusToResponseCode(code)
 }

sharedlibrary/documents.go

@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 	"strings"
 
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 //export CreateDocument
@@ -21,15 +21,15 @@ func CreateDocument(serverName *C.char, databaseId *C.char, collectionId *C.char
 		return ResponseServerInstanceNotFound
 	}
 
-	var document repositorymodels.Document
+	var document datastore.Document
 	err := json.NewDecoder(strings.NewReader(documentStr)).Decode(&document)
 	if err != nil {
 		return ResponseFailedToParseRequest
 	}
 
-	_, code := serverInstance.repository.CreateDocument(databaseIdStr, collectionIdStr, document)
+	_, code := serverInstance.dataStore.CreateDocument(databaseIdStr, collectionIdStr, document)
 
-	return repositoryStatusToResponseCode(code)
+	return dataStoreStatusToResponseCode(code)
 }
 
 //export GetDocument
@@ -45,8 +45,8 @@ func GetDocument(serverName *C.char, databaseId *C.char, collectionId *C.char, d
 		return C.CString("")
 	}
 
-	document, code := serverInstance.repository.GetDocument(databaseIdStr, collectionIdStr, documentIdStr)
-	if code != repositorymodels.StatusOk {
+	document, code := serverInstance.dataStore.GetDocument(databaseIdStr, collectionIdStr, documentIdStr)
+	if code != datastore.StatusOk {
 		return C.CString("")
 	}
 
@@ -69,8 +69,8 @@ func GetAllDocuments(serverName *C.char, databaseId *C.char, collectionId *C.cha
 		return C.CString("")
 	}
 
-	documents, code := serverInstance.repository.GetAllDocuments(databaseIdStr, collectionIdStr)
-	if code != repositorymodels.StatusOk {
+	documents, code := serverInstance.dataStore.GetAllDocuments(databaseIdStr, collectionIdStr)
+	if code != datastore.StatusOk {
 		return C.CString("")
 	}
 
@@ -95,19 +95,19 @@ func UpdateDocument(serverName *C.char, databaseId *C.char, collectionId *C.char
 		return ResponseServerInstanceNotFound
 	}
 
-	var document repositorymodels.Document
+	var document datastore.Document
 	err := json.Unmarshal([]byte(documentStr), &document)
 	if err != nil {
 		return ResponseFailedToParseRequest
 	}
 
-	code := serverInstance.repository.DeleteDocument(databaseIdStr, collectionIdStr, documentIdStr)
-	if code != repositorymodels.StatusOk {
-		return repositoryStatusToResponseCode(code)
+	code := serverInstance.dataStore.DeleteDocument(databaseIdStr, collectionIdStr, documentIdStr)
+	if code != datastore.StatusOk {
+		return dataStoreStatusToResponseCode(code)
 	}
 
-	_, code = serverInstance.repository.CreateDocument(databaseIdStr, collectionIdStr, document)
-	return repositoryStatusToResponseCode(code)
+	_, code = serverInstance.dataStore.CreateDocument(databaseIdStr, collectionIdStr, document)
+	return dataStoreStatusToResponseCode(code)
 }
 
 //export DeleteDocument
@@ -123,7 +123,7 @@ func DeleteDocument(serverName *C.char, databaseId *C.char, collectionId *C.char
 		return ResponseServerInstanceNotFound
 	}
 
-	code := serverInstance.repository.DeleteDocument(databaseIdStr, collectionIdStr, documentIdStr)
+	code := serverInstance.dataStore.DeleteDocument(databaseIdStr, collectionIdStr, documentIdStr)
 
-	return repositoryStatusToResponseCode(code)
+	return dataStoreStatusToResponseCode(code)
 }

sharedlibrary/shared.go

@@ -4,13 +4,12 @@ import (
 	"sync"
 
 	"github.com/pikami/cosmium/api"
-	"github.com/pikami/cosmium/internal/repositories"
-	repositorymodels "github.com/pikami/cosmium/internal/repository_models"
+	"github.com/pikami/cosmium/internal/datastore"
 )
 
 type ServerInstance struct {
-	server     *api.ApiServer
-	repository *repositories.DataRepository
+	server    *api.ApiServer
+	dataStore datastore.DataStore
 }
 
 var (
@@ -21,17 +20,18 @@ var (
 const (
 	ResponseSuccess = 0
 
-	ResponseUnknown                     = 100
-	ResponseFailedToParseConfiguration  = 101
-	ResponseFailedToLoadState           = 102
-	ResponseFailedToParseRequest        = 103
-	ResponseServerInstanceAlreadyExists = 104
-	ResponseServerInstanceNotFound      = 105
-	ResponseFailedToStartServer         = 106
+	ResponseUnknown                                   = 100
+	ResponseFailedToParseConfiguration                = 101
+	ResponseFailedToLoadState                         = 102
+	ResponseFailedToParseRequest                      = 103
+	ResponseServerInstanceAlreadyExists               = 104
+	ResponseServerInstanceNotFound                    = 105
+	ResponseFailedToStartServer                       = 106
+	ResponseCurentDataStoreDoesNotSupportStateLoading = 107
 
-	ResponseRepositoryNotFound   = 200
-	ResponseRepositoryConflict   = 201
-	ResponseRepositoryBadRequest = 202
+	ResponseDataStoreNotFound   = 200
+	ResponseDataStoreConflict   = 201
+	ResponseDataStoreBadRequest = 202
 )
 
 func getInstance(serverName string) (*ServerInstance, bool) {
@@ -61,16 +61,16 @@ func removeInstance(serverName string) {
 	delete(serverInstances, serverName)
 }
 
-func repositoryStatusToResponseCode(status repositorymodels.RepositoryStatus) int {
+func dataStoreStatusToResponseCode(status datastore.DataStoreStatus) int {
 	switch status {
-	case repositorymodels.StatusOk:
+	case datastore.StatusOk:
 		return ResponseSuccess
-	case repositorymodels.StatusNotFound:
-		return ResponseRepositoryNotFound
-	case repositorymodels.Conflict:
-		return ResponseRepositoryConflict
-	case repositorymodels.BadRequest:
-		return ResponseRepositoryBadRequest
+	case datastore.StatusNotFound:
+		return ResponseDataStoreNotFound
+	case datastore.Conflict:
+		return ResponseDataStoreConflict
+	case datastore.BadRequest:
+		return ResponseDataStoreBadRequest
 	default:
 		return ResponseUnknown
 	}

sharedlibrary/sharedlibrary.go

@@ -11,7 +11,7 @@ import (
 
 	"github.com/pikami/cosmium/api"
 	"github.com/pikami/cosmium/api/config"
-	"github.com/pikami/cosmium/internal/repositories"
+	mapdatastore "github.com/pikami/cosmium/internal/datastore/map_datastore"
 )
 
 //export CreateServerInstance
@@ -32,20 +32,20 @@ func CreateServerInstance(serverName *C.char, configurationJSON *C.char) int {
 	configuration.ApplyDefaultsToEmptyFields()
 	configuration.PopulateCalculatedFields()
 
-	repository := repositories.NewDataRepository(repositories.RepositoryOptions{
+	dataStore := mapdatastore.NewMapDataStore(mapdatastore.MapDataStoreOptions{
 		InitialDataFilePath: configuration.InitialDataFilePath,
 		PersistDataFilePath: configuration.PersistDataFilePath,
 	})
 
-	server := api.NewApiServer(repository, &configuration)
+	server := api.NewApiServer(dataStore, &configuration)
 	err = server.Start()
 	if err != nil {
 		return ResponseFailedToStartServer
 	}
 
 	addInstance(serverNameStr, &ServerInstance{
-		server:     server,
-		repository: repository,
+		server:    server,
+		dataStore: dataStore,
 	})
 
 	return ResponseSuccess
@@ -69,7 +69,7 @@ func GetServerInstanceState(serverName *C.char) *C.char {
 	serverNameStr := C.GoString(serverName)
 
 	if serverInstance, ok := getInstance(serverNameStr); ok {
-		stateJSON, err := serverInstance.repository.GetState()
+		stateJSON, err := serverInstance.dataStore.DumpToJson()
 		if err != nil {
 			return nil
 		}
@@ -85,11 +85,14 @@ func LoadServerInstanceState(serverName *C.char, stateJSON *C.char) int {
 	stateJSONStr := C.GoString(stateJSON)
 
 	if serverInstance, ok := getInstance(serverNameStr); ok {
-		err := serverInstance.repository.LoadStateJSON(stateJSONStr)
-		if err != nil {
-			return ResponseFailedToLoadState
+		if mapDS, ok := serverInstance.dataStore.(*mapdatastore.MapDataStore); ok {
+			err := mapDS.LoadStateJSON(stateJSONStr)
+			if err != nil {
+				return ResponseFailedToLoadState
+			}
+			return ResponseSuccess
 		}
-		return ResponseSuccess
+		return ResponseCurentDataStoreDoesNotSupportStateLoading
 	}
 
 	return ResponseServerInstanceNotFound