diff --git a/src/sql/resolver/expr/ob_raw_expr_deduce_type.cpp b/src/sql/resolver/expr/ob_raw_expr_deduce_type.cpp
index c71f49f428..c7b9b240fa 100644
--- a/src/sql/resolver/expr/ob_raw_expr_deduce_type.cpp
+++ b/src/sql/resolver/expr/ob_raw_expr_deduce_type.cpp
@@ -2441,9 +2441,13 @@ int ObRawExprDeduceType::visit(ObWinFunRawExpr &expr)
         }
       }
     } else {
-      expr.set_result_type(func_params.at(0)->get_result_type());
+      ObExprResType res_type = func_params.at(0)->get_result_type();
+      res_type.unset_result_flag(NOT_NULL_FLAG);
+      //set calc type for explain stmts and cases that the param0 is paramlized
+      res_type.set_calc_meta(res_type.get_obj_meta());
+      res_type.set_calc_accuracy(res_type.get_accuracy());
+      expr.set_result_type(res_type);
       expr.set_enum_set_values(func_params.at(0)->get_enum_set_values());
-      expr.unset_result_flag(NOT_NULL_FLAG);
     }
     // lead和lag函数的第三个参数，应当转换为第一个参数的类型，加cast，这里不能在执行层转。
     // bug: https://work.aone.alibaba-inc.com/issue/24115140