diff --git a/src/observer/sql/executor/execute_stage.cpp b/src/observer/sql/executor/execute_stage.cpp
index 5484fba454ea87c9fd0e3a0d5f73734aa6227761..a9fc784c55815536981c4abe2f3878742fab73d6 100644
--- a/src/observer/sql/executor/execute_stage.cpp
+++ b/src/observer/sql/executor/execute_stage.cpp
@@ -290,6 +290,8 @@ IndexScanOperator *try_to_create_index_scan_operator(FilterStmt *filter_stmt)
     if (left->type() == ExprType::FIELD && right->type() == ExprType::VALUE) {
     } else if (left->type() == ExprType::VALUE && right->type() == ExprType::FIELD) {
       std::swap(left, right);
+    } else {
+      continue;
     }
     FieldExpr &left_field_expr = *(FieldExpr *)left;
     const Field &field = left_field_expr.field();