Patch bugfix from 3.1.x.

src/sql/rewrite/ob_transform_outerjoin_limit_pushdown.cpp

@@ -102,9 +102,7 @@ int ObTransformOuterJoinLimitPushDown::check_basic(ObDMLStmt* stmt, OjLimitPushD
              select_stmt->has_group_by() || select_stmt->has_having() || select_stmt->has_rollup() ||
              select_stmt->has_window_function() || select_stmt->has_sequence() ||
              select_stmt->get_semi_infos().count() > 0 ||
-             // disable meaningless distinct co-exists with orderby cases.
-             // distinct with limit only is allowed and no need special handling.
-             (select_stmt->has_distinct() && select_stmt->has_order_by())) {
+             select_stmt->has_distinct()) {
     is_valid = false;
   } else if (OB_FAIL(check_limit(select_stmt, is_valid_limit))) {
     LOG_WARN("failed to check the validity of limit expr", K(ret));
@@ -421,16 +419,25 @@ int ObTransformOuterJoinLimitPushDown::check_validity_for_target_table(OjLimitPu
 int ObTransformOuterJoinLimitPushDown::do_transform(OjLimitPushDownHelper& helper)
 {
   int ret = OB_SUCCESS;
-  TableItem* target_view_table = NULL;
+  ObSelectStmt *ref_query = NULL;
   if (OB_ISNULL(helper.select_stmt_) || OB_ISNULL(helper.target_table_)) {
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("invalid parameter in helper", K(ret));
-  } else if (helper.need_create_view_ && OB_FAIL(prepare_view_table(helper.select_stmt_,
-                                             helper.target_table_,
+  } else if (OB_FAIL(remove_and_copy_condition_orderby(helper.select_stmt_,
                                                        helper.extracted_conditions_,
-                                             helper.saved_order_items_,
+                                                       helper.saved_order_items_))) {
+    LOG_WARN("failed to do remove and copy for condition and orderby", K(ret));
+  } else if (helper.need_create_view_ &&
+             OB_FAIL(ObTransformUtils::create_view_with_table(helper.select_stmt_,
+                                                              ctx_,
+                                                              helper.target_table_,
                                                               helper.view_table_))) {
     LOG_WARN("failed to prepare new view for pushing down", K(ret));
+  } else if (OB_ISNULL(helper.view_table_) ||
+            !helper.view_table_->is_generated_table() ||
+            OB_ISNULL(ref_query = helper.view_table_->ref_query_)) {
+    ret = OB_ERR_UNEXPECTED;
+    LOG_WARN("invalid view table", K(ret));
   } else if (OB_FAIL(pushdown_view_table(helper.select_stmt_,
                                         helper.view_table_,
                                         helper.extracted_conditions_,
@@ -449,32 +456,6 @@ int ObTransformOuterJoinLimitPushDown::do_transform(OjLimitPushDownHelper& helpe
   return ret;
 }
 
-int ObTransformOuterJoinLimitPushDown::prepare_view_table(ObSelectStmt* stmt, TableItem* target_table,
-    ObIArray<ObRawExpr*>& extracted_conditions, ObIArray<OrderItem>& saved_order_items, TableItem*& view_table)
-{
-  int ret = OB_SUCCESS;
-  ObSelectStmt* ref_query = NULL;
-  // before warpping with view, remove extracted condition exprs in upper stmt,
-  // and do condition exprs copy avoid being modified by create_view_with_table,
-  // which will be added back to the created view later.
-  // order by exprs have been copied at former collection stage.
-  if (OB_ISNULL(stmt) || OB_ISNULL(target_table)) {
-    ret = OB_ERR_UNEXPECTED;
-    LOG_WARN("invalid stmt", K(ret));
-  } else if (OB_FAIL(remove_and_copy_condition_orderby(stmt, extracted_conditions, saved_order_items))) {
-    LOG_WARN("failed to do remove and copy for condition and orderby", K(ret));
-  } else if (OB_FAIL(ObTransformUtils::create_view_with_table(stmt, ctx_, target_table, view_table))) {
-    LOG_WARN("failed to create view with table", K(ret));
-  } else if (OB_ISNULL(view_table) || !view_table->is_generated_table() ||
-             OB_ISNULL(ref_query = view_table->ref_query_)) {
-    ret = OB_ERR_UNEXPECTED;
-    LOG_WARN("get unexpected view table", K(ret), K(*view_table));
-  } else {
-    // do nothing
-  }
-  return ret;
-}
-
 int ObTransformOuterJoinLimitPushDown::remove_and_copy_condition_orderby(
     ObSelectStmt* stmt, ObIArray<ObRawExpr*>& extracted_conditions, ObIArray<OrderItem>& saved_order_items)
 {
@@ -532,8 +513,6 @@ int ObTransformOuterJoinLimitPushDown::add_condition_expr_for_viewtable(
   if (OB_ISNULL(generated_view)) {
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("invalid generated_view", K(ret));
-  } else if (OB_FAIL(append(generated_view->get_condition_exprs(), extracted_conditions))) {
-    LOG_WARN("failed to append condition exprs back", K(ret));
   } else if (need_rename) {
     // renaming for saved condition expr from upper level
     // after pushdown into generated_view condition exprs.
@@ -541,7 +520,10 @@ int ObTransformOuterJoinLimitPushDown::add_condition_expr_for_viewtable(
     ObSEArray<ObRawExpr*, 16> new_column_exprs;
     for (int64_t i = 0; OB_SUCC(ret) && i < extracted_conditions.count(); ++i) {
       ObRawExpr* expr = extracted_conditions.at(i);
-      if (OB_FAIL(ObRawExprUtils::extract_column_exprs(expr, old_column_exprs))) {
+      if (OB_ISNULL(expr)) {
+        ret = OB_ERR_UNEXPECTED;
+        LOG_WARN("invalid condition", K(ret));
+      } else if (OB_FAIL(ObRawExprUtils::extract_column_exprs(expr, old_column_exprs))) {
         LOG_WARN("failed to extract column expr", K(ret));
       } else if (OB_FAIL(ObTransformUtils::convert_column_expr_to_select_expr(
                      old_column_exprs, *generated_view, new_column_exprs))) {
@@ -552,6 +534,11 @@ int ObTransformOuterJoinLimitPushDown::add_condition_expr_for_viewtable(
       }
     }
   }
+  if (OB_SUCC(ret)) {
+    if (OB_FAIL(append(generated_view->get_condition_exprs(), extracted_conditions))) {
+      LOG_WARN("failed to append condition exprs back", K(ret));
+    } else {/* do nothing */}
+  }
   return ret;
 }
 
@@ -562,37 +549,34 @@ int ObTransformOuterJoinLimitPushDown::add_orderby_for_viewtable(
   if (OB_ISNULL(generated_view) || OB_ISNULL(upper_stmt)) {
     ret = OB_ERR_UNEXPECTED;
     LOG_WARN("invalid parameter", K(ret));
-  } else if (!need_rename) {
-    // directly assign saved order items to generated_view
-    generated_view->get_order_items().reset();
-    if (OB_FAIL(generated_view->get_order_items().assign(saved_order_items))) {
-      LOG_WARN("assign new order items failed", K(ret));
-    } else { /* do nothing */
-    }
-  } else {
-    // single table item generated_table into here.
+  } else if (need_rename) {
     // order by column needs to be renamed before moving
     // from upper_stmt to inner generated_view.
+    for (int64_t i = 0; OB_SUCC(ret) && i < saved_order_items.count(); i++) {
       ObSEArray<ObRawExpr*, 16> old_order_exprs;
       ObSEArray<ObRawExpr*, 16> new_order_exprs;
-    if (OB_FAIL(append(generated_view->get_order_items(), upper_stmt->get_order_items()))) {
-      LOG_WARN("failed to append order item", K(ret));
-    } else {
-      for (int64_t i = 0; OB_SUCC(ret) && i < upper_stmt->get_order_item_size(); ++i) {
-        if (OB_FAIL(old_order_exprs.push_back(upper_stmt->get_order_items().at(i).expr_))) {
-          LOG_WARN("failed to append order item", K(ret));
-        }
-      }
-      if (OB_SUCC(ret)) {
-        if (OB_FAIL(ObTransformUtils::convert_column_expr_to_select_expr(
-                old_order_exprs, *generated_view, new_order_exprs))) {
+      if (OB_ISNULL(saved_order_items.at(i).expr_)) {
+        ret = OB_ERR_UNEXPECTED;
+        LOG_WARN("invalid expr", K(ret));
+      } else if (OB_FAIL(ObRawExprUtils::extract_column_exprs(saved_order_items.at(i).expr_,
+                                                              old_order_exprs))) {
+        LOG_WARN("failed to extract column expr", K(ret));
+      } else if (OB_FAIL(ObTransformUtils::convert_column_expr_to_select_expr(old_order_exprs,
+                                                                              *generated_view,
+                                                                              new_order_exprs))) {
         LOG_WARN("failed to convert columnexpr to select expr", K(ret));
-        } else if (OB_FAIL(ObTransformUtils::replace_expr_for_order_item(
-                       old_order_exprs, new_order_exprs, generated_view->get_order_items()))) {
+      } else if (OB_FAIL(ObTransformUtils::replace_expr(old_order_exprs,
+                                                        new_order_exprs,
+                                                        saved_order_items.at(i).expr_))) {
         LOG_WARN("failed to replace expr for order item", K(ret));
-        } else { /* do nothing */
+      } else {/* do nothing */
+      }
     }
   }
+  if (OB_SUCC(ret)) {
+    if (OB_FAIL(append(generated_view->get_order_items(), saved_order_items))) {
+      LOG_WARN("failed to append order item", K(ret));
+    } else {/* do nothing */
     }
   }
   return ret;

src/sql/rewrite/ob_transform_outerjoin_limit_pushdown.h

@@ -88,9 +88,6 @@ private:
 
   int check_validity_for_target_table(OjLimitPushDownHelper& helper, bool& is_valid);
 
-  int prepare_view_table(ObSelectStmt* stmt, TableItem* target_table, ObIArray<ObRawExpr*>& extracted_conditions,
-      ObIArray<OrderItem>& saved_order_items, TableItem*& view_table);
-
   int pushdown_view_table(ObSelectStmt* stmt, TableItem* target_table, ObIArray<ObRawExpr*>& extracted_conditions,
       ObIArray<OrderItem>& saved_order_items, bool need_rename, bool is_limit_only);