Fix view merge bug when there is a rand() function in select items of view.

src/sql/rewrite/ob_transform_groupby_placement.cpp

@@ -1548,6 +1548,7 @@ int ObTransformGroupByPlacement::check_groupby_pullup_validity(ObDMLStmt* stmt,
 {
   int ret = OB_SUCCESS;
   bool can_pullup = false;
+  bool has_rand = false;
   if (OB_ISNULL(stmt) || OB_ISNULL(table)) {
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("param has null", K(stmt), K(table), K(ret));
@@ -1574,6 +1575,11 @@ int ObTransformGroupByPlacement::check_groupby_pullup_validity(ObDMLStmt* stmt,
       LOG_WARN("failed to check null propagate select expr", K(ret));
     } else if (!can_pullup) {
       // do nothing
+    } else if (OB_FAIL(sub_stmt->has_rand(has_rand))) {
+      LOG_WARN("failed to check stmt has rand func", K(ret));
+      // stmt不能包含rand函数 https://work.aone.alibaba-inc.com/issue/35875561
+    } else if (!(can_pullup = !has_rand)) {
+      // do nothing
     } else if (OB_FALSE_IT(helper.need_merge_ = sub_stmt->get_stmt_hint().enable_view_merge())) {
     } else if (OB_FAIL(valid_views.push_back(helper))) {
       LOG_WARN("failed to push back group stmt index", K(ret));

src/sql/rewrite/ob_transform_view_merge.cpp

@@ -346,7 +346,15 @@ int ObTransformViewMerge::check_can_be_unnested(
         LOG_WARN("NULL expr", K(ret));
       } else if (expr->has_flag(CNT_SUB_QUERY)) {
         can_be = false;
-      } else { /*do nothing*/
+      }
+    }
+    // stmt不能包含rand函数 https://work.aone.alibaba-inc.com/issue/35875561
+    if (OB_SUCC(ret) && can_be) {
+      bool has_rand = false;
+      if (OB_FAIL(child_stmt->has_rand(has_rand))) {
+        LOG_WARN("failed to get rand flag", K(ret));
+      } else {
+        can_be = !has_rand;
       }
     }
   }