Handle insert...returning... queries

enginetest/queries/insert_queries.go

@@ -2276,6 +2276,26 @@ var InsertScripts = []ScriptTest{
 			},
 		},
 	},
+	{
+		Name: "insert...returning... statements",
+		SetUpScript: []string{
+			"CREATE TABLE animals (id int, name varchar(20))",
+		},
+		Assertions: []ScriptTestAssertion{
+			{
+				Query:    "insert into animals (id) values (2) returning id",
+				Expected: []sql.Row{{2}},
+			},
+			{
+				Query:    "insert into animals(id,name) values (1, 'Dog'),(2,'Lion'),(3,'Tiger'),(4,'Leopard') returning id, id+id",
+				Expected: []sql.Row{{1, 2}, {2, 4}, {3, 6}, {4, 8}},
+			},
+			{
+				Query:    "insert into animals set id=1,name='Bear' returning id,name",
+				Expected: []sql.Row{{1, "Bear"}},
+			},
+		},
+	},
 }
 
 var InsertDuplicateKeyKeyless = []ScriptTest{

server/handler.go

@@ -157,7 +157,10 @@ func (h *Handler) ComPrepare(ctx context.Context, c *mysql.Conn, query string, p
 // than they will at execution time.
 func nodeReturnsOkResultSchema(node sql.Node) bool {
 	switch node.(type) {
-	case *plan.InsertInto, *plan.Update, *plan.UpdateJoin, *plan.DeleteFrom:
+	case *plan.InsertInto:
+		insertNode, _ := node.(*plan.InsertInto)
+		return insertNode.Returning == nil
+	case *plan.Update, *plan.UpdateJoin, *plan.DeleteFrom:
 		return true
 	}
 	return false

sql/plan/insert.go

@@ -72,7 +72,7 @@ type InsertInto struct {
 	LiteralValueSource bool
 
 	// Returning is a list of expressions to return after the insert operation. This feature is not supported
-	// in MySQL's syntax, but is exposed through PostgreSQL's syntax.
+	// in MySQL's syntax, but is exposed through PostgreSQL's and MariaDB's syntax.
 	Returning []sql.Expression
 
 	// FirstGenerateAutoIncRowIdx is the index of the first row inserted that increments last_insert_id.