diff --git a/schema/validator.go b/schema/validator.go
index 5df56c8..84cb951 100644
--- a/schema/validator.go
+++ b/schema/validator.go
@@ -255,7 +255,7 @@ func (c *ContextValidator) visitActions(actions []Action) error {
 				if err != nil {
 					return fmt.Errorf("%w: %s", err, statement)
 				}
-				if _, err := astTree.ToSQL(); err != nil {
+				if _, err := tree.SafeToSQL(astTree); err != nil {
 					return fmt.Errorf("%w: %s", err, statement)
 				}
 				// TODO: validate reference in SQL statement