[cp]fix some bugs

src/sql/resolver/dml/ob_dml_stmt.cpp

@@ -2845,13 +2845,23 @@ int ObDMLStmt::get_view_output(
     LOG_WARN("the table is not a generated table", K(ret));
   } else if (OB_FAIL(get_column_exprs(table.table_id_, columns))) {
     LOG_WARN("failed to get column exprs", K(ret));
-  } else if (OB_FAIL(append(column_list, columns))) {
-    LOG_WARN("failed to append columns", K(ret));
-  } else if (OB_FAIL(table.ref_query_->get_select_exprs(select_list))) {
-    LOG_WARN("failed to get select list", K(ret));
-  } else if (OB_UNLIKELY(select_list.count() != column_list.count())) {
-    ret = OB_ERR_UNEXPECTED;
-    LOG_WARN("the select list does match the column list", K(ret), K(select_list.count()), K(column_list.count()));
+  } else {
+    for (int64_t i = 0; OB_SUCC(ret) && i < columns.count(); ++i) {
+      ObColumnRefRawExpr *col_expr = columns.at(i);
+      int64_t idx = OB_INVALID_INDEX;
+      if (OB_ISNULL(col_expr)) {
+        ret = OB_ERR_UNEXPECTED;
+        LOG_WARN("get unexpected null", K(ret));
+      } else if (OB_FALSE_IT(idx = col_expr->get_column_id() - OB_APP_MIN_COLUMN_ID)) {
+      } else if (idx < 0 || idx >= table.ref_query_->get_select_item_size()) {
+        ret = OB_ERR_UNEXPECTED;
+        LOG_WARN("get invalid idx", K(ret), K(idx));
+      } else if (OB_FAIL(select_list.push_back(table.ref_query_->get_select_item(idx).expr_))) {
+        LOG_WARN("failed to push back select expr", K(ret));
+      } else if (OB_FAIL(column_list.push_back(col_expr))) {
+        LOG_WARN("failed to push back column expr", K(ret));
+      }
+    }
   }
   return ret;
 }

src/sql/rewrite/ob_transform_simplify.cpp

@@ -3009,8 +3009,8 @@ int ObTransformSimplify::try_remove_redundent_select(ObSelectStmt& stmt, ObSelec
 /**
  * @brief check_subquery_valid
  * check subquery return equal one row, if empty do nothing
- * has limit 可能使结果为空不做改写;
- * select ... where rownum >2; rownum不包含1必空，包含判断较难，暂不处理
+ * has limit may return empty result, do nothing:
+ * select ... where rownum >2;
  * subquery should in format of:
  * 1. select ... from dual;  no where condition
  * 2. select aggr() ...;  <- no group by, no having
@@ -3030,7 +3030,8 @@ int ObTransformSimplify::check_subquery_valid(ObSelectStmt& stmt, bool& is_valid
       // do nothing
     } else if (0 == stmt.get_from_item_size() && 0 == stmt.get_condition_size()) {
       is_valid = true;
-    } else if (0 == stmt.get_group_expr_size() && 0 == stmt.get_having_expr_size() && sel_expr->has_flag(CNT_AGG)) {
+    } else if (0 == stmt.get_group_expr_size() && 0 == stmt.get_rollup_expr_size() &&
+               0 == stmt.get_having_expr_size() && sel_expr->has_flag(CNT_AGG)) {
       is_valid = true;
     }
   }