[xml bugfix] 1. xmltype empty variable problem under pl 2. xmlelement anti-spelling label case problem

src/sql/plan_cache/ob_sql_parameterization.cpp

@@ -1772,6 +1772,13 @@ int ObSqlParameterization::mark_tree(ParseNode *tree ,SqlInfo &sql_info)
         if (OB_FAIL(mark_args(node[1], mark_arr, ARGS_NUMBER_THREE, sql_info))) {
           SQL_PC_LOG(WARN, "fail to mark arg", K(ret));
         }
+      } else if (0 == func_name.case_compare("xmlserialize")
+            && (10 == node[1]->num_child_)) {
+        const int64_t ARGS_NUMBER_TEN = 10;
+        bool mark_arr[ARGS_NUMBER_TEN] = {1, 0, 1, 1, 1, 1, 1, 1, 1, 1}; //0表示参数化, 1 表示不参数化
+        if (OB_FAIL(mark_args(node[1], mark_arr, ARGS_NUMBER_TEN, sql_info))) {
+          SQL_PC_LOG(WARN, "fail to mark weight_string arg", K(ret));
+        }
       }else if (0 == func_name.case_compare("weight_string")
           && (5 == node[1]->num_child_)) {
         const int64_t ARGS_NUMBER_FIVE = 5;

src/sql/resolver/expr/ob_raw_expr_printer.cpp

@@ -4539,10 +4539,10 @@ int ObRawExprPrinter::print_xml_element_expr(ObSysFunRawExpr *expr)
 
         if (OB_SUCC(ret) && format_type == 0) {
           if (buf_[cur_pos] == '\'') {
-             buf_[cur_pos] = ' ';
+             buf_[cur_pos] = '"';
           }
           if (buf_[new_pos - 1] == '\'') {
-             buf_[new_pos - 1] = ' ';
+             buf_[new_pos - 1] = '"';
           }
         }