Fix ORDER BY clauses in ARRAY subqueries

BemiHQ · Feb 12, 2025 · 1b3a1e1 · 1b3a1e1
1 parent 93d9430
commit 1b3a1e1
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Showing 2 changed files with 18 additions and 3 deletions.
diff --git a/src/query_handler_test.go b/src/query_handler_test.go
@@ -839,6 +839,13 @@ func TestHandleQuery(t *testing.T) {
 			"values":      {"10", "bemidb"},
 		},
 
+		// ORDER BY
+		"SELECT ARRAY(SELECT 1 FROM pg_enum ORDER BY enumsortorder) AS array": {
+			"description": {"array"},
+			"types":       {Uint32ToString(pgtype.Int4ArrayOID)},
+			"values":      {"{}"},
+		},
+
 		// Table alias
 		"SELECT pg_shadow.usename FROM pg_shadow": {
 			"description": {"usename"},

diff --git a/src/query_remapper.go b/src/query_remapper.go
@@ -391,11 +391,9 @@ func (remapper *QueryRemapper) remapJoinExpressions(selectStatement *pgQuery.Sel
 		node.GetJoinExpr().Quals = remapper.remapTypeCastsInNode(node.GetJoinExpr().Quals) // recursion
 
 		// DuckDB doesn't support non-INNER JOINs with ON clauses that reference columns from outer tables:
-		//
 		//   SELECT (
 		//     SELECT 1 AS test FROM (SELECT 1 AS inner_val) LEFT JOIN (SELECT NULL) ON inner_val = *outer_val*
 		//   ) FROM (SELECT 1 AS outer_val)
-		//
 		//   > "Non-inner join on correlated columns not supported"
 		//
 		// References:
@@ -457,8 +455,18 @@ func (remapper *QueryRemapper) remapSelect(selectStatement *pgQuery.SelectStmt,
 			remapper.remapCaseExpressions(selectStatement, indentLevel) // recursive
 		} else if targetNode.GetResTarget().Val.GetSubLink() != nil {
 			// Nested SELECT
-			subSelect := targetNode.GetResTarget().Val.GetSubLink().Subselect.GetSelectStmt()
+			subLink := targetNode.GetResTarget().Val.GetSubLink()
+			subSelect := subLink.Subselect.GetSelectStmt()
 			remapper.remapSelectStatement(subSelect, indentLevel+1) // recursive
+
+			// DuckDB doesn't work with ORDER BY in ARRAY subqueries:
+			//   SELECT ARRAY(SELECT 1 FROM pg_enum ORDER BY enumsortorder)
+			//   > Referenced column "enumsortorder" not found in FROM clause!
+			//
+			// Remove ORDER BY from ARRAY subqueries
+			if subLink.SubLinkType == pgQuery.SubLinkType_ARRAY_SUBLINK && subSelect.SortClause != nil {
+				subSelect.SortClause = nil
+			}
 		} else if targetNode.GetResTarget().Val.GetCoalesceExpr() != nil {
 			// COALESCE(value1, value2, ...)
 			coalesceExpr := targetNode.GetResTarget().Val.GetCoalesceExpr()