Add support for expressions in SELECT clause

parsers/models.go

@@ -34,6 +34,7 @@ const (
 	SelectItemTypeConstant
 	SelectItemTypeFunctionCall
 	SelectItemTypeSubQuery
+	SelectItemTypeExpression
 )
 
 type SelectItem struct {

parsers/nosql/nosql.peg

@@ -204,7 +204,7 @@ TopClause <- Top ws count:Integer {
     return count, nil
 }
 
-FromClause <- From ws table:TableName selectItem:(ws In ws column:SelectItem { return column, nil }) {
+FromClause <- From ws table:TableName selectItem:(ws In ws column:SelectItemWithAlias { return column, nil }) {
     tableTyped := table.(parsers.Table)
 
     if selectItem != nil {
@@ -213,7 +213,7 @@ FromClause <- From ws table:TableName selectItem:(ws In ws column:SelectItem { r
 	}
 
 	return tableTyped, nil
-} / From ws column:SelectItem {
+} / From ws column:SelectItemWithAlias {
     tableSelectItem := column.(parsers.SelectItem)
     table := parsers.Table{
         Value: tableSelectItem.Alias,
@@ -251,7 +251,7 @@ SubQuerySelectItem <- subQuery:SubQuery asClause:(ws alias:AsClause { return ali
     return selectItem, nil
 }
 
-JoinClause <- Join ws table:TableName ws In ws column:SelectItem {
+JoinClause <- Join ws table:TableName ws In ws column:SelectItemWithAlias {
     return makeJoin(table, column)
 } / Join ws subQuery:SubQuerySelectItem {
     return makeJoin(nil, subQuery)
@@ -269,11 +269,34 @@ SelectAsterisk <- "*" {
     return makeColumnList(selectItem, make([]interface{}, 0))
 }
 
-ColumnList <- column:SelectItem other_columns:(ws "," ws coll:SelectItem {return coll, nil })* {
+ColumnList <- column:ExpressionOrSelectItem other_columns:(ws "," ws coll:ExpressionOrSelectItem {return coll, nil })* {
     return makeColumnList(column, other_columns)
 }
 
-SelectValueSpec <- "VALUE"i ws column:SelectItem {
+ExpressionOrSelectItem <- expression:OrExpression asClause:AsClause? {
+    switch typedValue := expression.(type) {
+    case parsers.ComparisonExpression, parsers.LogicalExpression:
+        selectItem := parsers.SelectItem{
+            Type: parsers.SelectItemTypeExpression,
+            Value: typedValue,
+        }
+
+        if aliasValue, ok := asClause.(string); ok {
+            selectItem.Alias = aliasValue
+        }
+
+        return selectItem, nil
+    case parsers.SelectItem:
+        if aliasValue, ok := asClause.(string); ok {
+            typedValue.Alias = aliasValue
+        }
+        return typedValue, nil
+    default:
+        return typedValue, nil
+    }
+} / item:SelectItemWithAlias { return item, nil }
+
+SelectValueSpec <- "VALUE"i ws column:SelectItemWithAlias {
     selectItem := column.(parsers.SelectItem)
 	selectItem.IsTopLevel = true
     return makeColumnList(selectItem, make([]interface{}, 0))
@@ -306,7 +329,15 @@ SelectProperty <- name:Identifier path:(DotFieldAccess / ArrayFieldAccess)* {
     return makeSelectItem(name, path, parsers.SelectItemTypeField)
 }
 
-SelectItem <- selectItem:(SubQuerySelectItem / Literal / FunctionCall / SelectArray / SelectObject / SelectProperty) asClause:AsClause? {
+SelectItemWithAlias <- selectItem:SelectItem asClause:AsClause? {
+    item := selectItem.(parsers.SelectItem)
+    if aliasValue, ok := asClause.(string); ok {
+        item.Alias = aliasValue
+    }
+    return item, nil
+}
+
+SelectItem <- selectItem:(SubQuerySelectItem / Literal / FunctionCall / SelectArray / SelectObject / SelectProperty) {
     var itemResult parsers.SelectItem
     switch typedValue := selectItem.(type) {
     case parsers.SelectItem:
@@ -323,10 +354,6 @@ SelectItem <- selectItem:(SubQuerySelectItem / Literal / FunctionCall / SelectAr
         }
     }
 
-	if aliasValue, ok := asClause.(string); ok {
-		itemResult.Alias = aliasValue
-	}
-
 	return itemResult, nil
 }
 

parsers/nosql/select_test.go

@@ -195,4 +195,73 @@ func Test_Parse_Select(t *testing.T) {
 			},
 		)
 	})
+
+	t.Run("Should parse comparison expressions in SELECT", func(t *testing.T) {
+		testQueryParse(
+			t,
+			`SELECT c["id"] = "123", c["pk"] > 456 FROM c`,
+			parsers.SelectStmt{
+				SelectItems: []parsers.SelectItem{
+					{
+						Type: parsers.SelectItemTypeExpression,
+						Value: parsers.ComparisonExpression{
+							Operation: "=",
+							Left:      testutils.SelectItem_Path("c", "id"),
+							Right:     testutils.SelectItem_Constant_String("123"),
+						},
+					},
+					{
+						Type: parsers.SelectItemTypeExpression,
+						Value: parsers.ComparisonExpression{
+							Operation: ">",
+							Left:      testutils.SelectItem_Path("c", "pk"),
+							Right:     testutils.SelectItem_Constant_Int(456),
+						},
+					},
+				},
+				Table: parsers.Table{SelectItem: testutils.SelectItem_Path("c")},
+			},
+		)
+	})
+
+	t.Run("Should parse logical expressions in SELECT", func(t *testing.T) {
+		testQueryParse(
+			t,
+			`SELECT c["id"] = "123" OR c["pk"] > 456, c["isCool"] AND c["hasRizz"] AS isRizzler FROM c`,
+			parsers.SelectStmt{
+				SelectItems: []parsers.SelectItem{
+					{
+						Type: parsers.SelectItemTypeExpression,
+						Value: parsers.LogicalExpression{
+							Operation: parsers.LogicalExpressionTypeOr,
+							Expressions: []interface{}{
+								parsers.ComparisonExpression{
+									Operation: "=",
+									Left:      testutils.SelectItem_Path("c", "id"),
+									Right:     testutils.SelectItem_Constant_String("123"),
+								},
+								parsers.ComparisonExpression{
+									Operation: ">",
+									Left:      testutils.SelectItem_Path("c", "pk"),
+									Right:     testutils.SelectItem_Constant_Int(456),
+								},
+							},
+						},
+					},
+					{
+						Type:  parsers.SelectItemTypeExpression,
+						Alias: "isRizzler",
+						Value: parsers.LogicalExpression{
+							Operation: parsers.LogicalExpressionTypeAnd,
+							Expressions: []interface{}{
+								testutils.SelectItem_Path("c", "isCool"),
+								testutils.SelectItem_Path("c", "hasRizz"),
+							},
+						},
+					},
+				},
+				Table: parsers.Table{SelectItem: testutils.SelectItem_Path("c")},
+			},
+		)
+	})
 }

query_executors/memory_executor/common.go

@@ -69,6 +69,19 @@ func (r rowContext) resolveSelectItem(selectItem parsers.SelectItem) interface{}
 		return nil
 	}
 
+	if selectItem.Type == parsers.SelectItemTypeExpression {
+		if typedExpression, ok := selectItem.Value.(parsers.ComparisonExpression); ok {
+			return r.filters_ComparisonExpression(typedExpression)
+		}
+
+		if typedExpression, ok := selectItem.Value.(parsers.LogicalExpression); ok {
+			return r.filters_LogicalExpression(typedExpression)
+		}
+
+		logger.ErrorLn("parsers.SelectItem has incorrect Value type (expected parsers.ComparisonExpression)")
+		return nil
+	}
+
 	return r.selectItem_SelectItemTypeField(selectItem)
 }
 

query_executors/memory_executor/comparison_expression_test.go

@@ -0,0 +1,92 @@
+package memoryexecutor_test
+
+import (
+	"testing"
+
+	"github.com/pikami/cosmium/parsers"
+	memoryexecutor "github.com/pikami/cosmium/query_executors/memory_executor"
+	testutils "github.com/pikami/cosmium/test_utils"
+)
+
+func Test_Execute_Expressions(t *testing.T) {
+	mockData := []memoryexecutor.RowType{
+		map[string]interface{}{"id": "123", "age": 10, "isCool": true},
+		map[string]interface{}{"id": "456", "age": 20, "isCool": false},
+		map[string]interface{}{"id": "789", "age": 30, "isCool": true},
+	}
+
+	t.Run("Should execute comparison expressions in SELECT", func(t *testing.T) {
+		testQueryExecute(
+			t,
+			parsers.SelectStmt{
+				SelectItems: []parsers.SelectItem{
+					{
+						Path: []string{"c", "id"},
+						Type: parsers.SelectItemTypeField,
+					},
+					{
+						Alias: "isAdult",
+						Type:  parsers.SelectItemTypeExpression,
+						Value: parsers.ComparisonExpression{
+							Operation: ">=",
+							Left:      testutils.SelectItem_Path("c", "age"),
+							Right:     testutils.SelectItem_Constant_Int(18),
+						},
+					},
+					{
+						Alias: "isNotCool",
+						Type:  parsers.SelectItemTypeExpression,
+						Value: parsers.ComparisonExpression{
+							Operation: "!=",
+							Left:      testutils.SelectItem_Path("c", "isCool"),
+							Right:     testutils.SelectItem_Constant_Bool(true),
+						},
+					},
+				},
+				Table: parsers.Table{SelectItem: testutils.SelectItem_Path("c")},
+			},
+			mockData,
+			[]memoryexecutor.RowType{
+				map[string]interface{}{"id": "123", "isAdult": false, "isNotCool": false},
+				map[string]interface{}{"id": "456", "isAdult": true, "isNotCool": true},
+				map[string]interface{}{"id": "789", "isAdult": true, "isNotCool": false},
+			},
+		)
+	})
+
+	t.Run("Should execute logical expressions in SELECT", func(t *testing.T) {
+		testQueryExecute(
+			t,
+			parsers.SelectStmt{
+				SelectItems: []parsers.SelectItem{
+					{
+						Path: []string{"c", "id"},
+						Type: parsers.SelectItemTypeField,
+					},
+					{
+						Alias: "isCoolAndAdult",
+						Type:  parsers.SelectItemTypeExpression,
+						Value: parsers.LogicalExpression{
+							Operation: parsers.LogicalExpressionTypeAnd,
+							Expressions: []interface{}{
+								testutils.SelectItem_Path("c", "isCool"),
+								parsers.ComparisonExpression{
+									Operation: ">=",
+									Left:      testutils.SelectItem_Path("c", "age"),
+									Right:     testutils.SelectItem_Constant_Int(18),
+								},
+							},
+						},
+					},
+				},
+				Table: parsers.Table{SelectItem: testutils.SelectItem_Path("c")},
+			},
+			mockData,
+			[]memoryexecutor.RowType{
+				map[string]interface{}{"id": "123", "isCoolAndAdult": false},
+				map[string]interface{}{"id": "456", "isCoolAndAdult": false},
+				map[string]interface{}{"id": "789", "isCoolAndAdult": true},
+			},
+		)
+	})
+}