bugfix : null in json expr clause has core dump in fast parser

src/objit/include/objit/common/ob_item_type.h

@@ -791,6 +791,7 @@ typedef enum ObItemType
   T_FUN_ORA_JSON_OBJECTAGG = 1685,
   T_FUN_SYS_JSON_EXISTS = 1686,
   T_FUN_SYS_TREAT = 1687,
+  T_NULLX_CLAUSE = 1688,   // null clause on json expr
 
   ///< @note add new oracle only function type before this line
 

src/sql/plan_cache/ob_sql_parameterization.cpp

@@ -253,6 +253,7 @@ int ObSqlParameterization::is_fast_parse_const(TransformTreeCtx &ctx)
                                     || T_QUESTIONMARK == ctx.tree_->type_
                                     || T_COLLATION == ctx.tree_->type_
                                     || T_CAST_ARGUMENT == ctx.tree_->type_
+                                    || T_NULLX_CLAUSE == ctx.tree_->type_
                                     || (T_SFU_INT == ctx.tree_->type_ && -1 != ctx.tree_->value_)
                                     || T_SFU_DECIMAL == ctx.tree_->type_);
       }
@@ -1459,8 +1460,9 @@ int ObSqlParameterization::add_not_param_flag(const ParseNode *node, SqlInfo &sq
     } else if (OB_FAIL(sql_info.not_param_index_.add_member(node->value_))) {
       SQL_PC_LOG(WARN, "failed to add member", K(node->value_));
     }
-  } else if (T_CAST_ARGUMENT == node->type_
+  } else if (T_CAST_ARGUMENT == node->type_        //如果是cast类型，则需要添加N个cast节点对应的常数, 因为正常parse不识别为常量, 但fast parse时会识别为常量
-             || T_COLLATION == node->type_) { //如果是cast类型，则需要添加N个cast节点对应的常数, 因为正常parse不识别为常量, 但fast parse时会识别为常量
+             || T_COLLATION == node->type_
+             || T_NULLX_CLAUSE == node->type_) { // deal null clause on json expr
     for (int i = 0; OB_SUCC(ret) && i < node->param_num_; ++i) {
       if (OB_FAIL(sql_info.not_param_index_.add_member(sql_info.total_++))) {
         SQL_PC_LOG(WARN, "failed to add member", K(sql_info.total_));

src/sql/resolver/expr/ob_raw_expr_resolver_impl.cpp

@@ -931,6 +931,15 @@ int ObRawExprResolverImpl::do_recursive_resolve(const ParseNode *node, ObRawExpr
         }
         break;
       }
+      case T_NULLX_CLAUSE: {
+        modification_type_to_int(const_cast<ParseNode&>(*node));
+        // deal node
+        if (OB_FAIL(SMART_CALL(recursive_resolve(node, expr)))) {
+          LOG_WARN("fail to process node with children only", K(ret),
+              K(node->type_), K(node));
+        }
+        break;
+      }
       case T_FUN_SYS_REGEXP_LIKE:
       case T_FUN_SYS: {
         if (OB_FAIL(process_fun_sys_node(node, expr))) {
@@ -5350,6 +5359,12 @@ int ObRawExprResolverImpl::pre_check_json_path_valid(const ParseNode *node)
   return ret;
 }
 
+// json expr change T_NULLX_CLAUSE to T_INT
+void ObRawExprResolverImpl::modification_type_to_int(ParseNode &node)
+{
+  node.type_ = T_INT;
+}
+
 int ObRawExprResolverImpl::process_json_value_node(const ParseNode *node, ObRawExpr *&expr)
 {
   INIT_SUCC(ret);

src/sql/resolver/expr/ob_raw_expr_resolver_impl.h

@@ -122,6 +122,7 @@ private:
   int process_json_exists_node(const ParseNode *node, ObRawExpr *&expr);
   int process_json_array_node(const ParseNode *node, ObRawExpr *&expr);
   int process_json_mergepatch_node(const ParseNode *node, ObRawExpr *&expr);
+  static void modification_type_to_int(ParseNode &node);
   int process_fun_sys_node(const ParseNode *node, ObRawExpr *&expr);
   int process_dll_udf_node(const ParseNode *node, ObRawExpr *&expr);
   int process_agg_udf_node(const ParseNode *node,