hcq/oceanbase
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Fix query push down and add subquery handling

Browse Source
This commit is contained in:
obdev
2021-07-11 19:45:11 +08:00
committed by wangzelin.wzl
parent 49d67f8644
commit 7dcf2baa4e
5 changed files with 92 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

56
src/sql/rewrite/ob_transform_query_push_down.cpp
View File

@ -342,6 +342,10 @@ int ObTransformQueryPushDown::check_select_item_push_down(ObSelectStmt* select_s
if (OB_ISNULL(select_stmt) || OB_ISNULL(view_stmt)) {
ret = OB_INVALID_ARGUMENT;
LOG_WARN("stmt is NULL", K(select_stmt), K(view_stmt), K(ret));
} else if (OB_FAIL(check_select_item_subquery(*select_stmt, *view_stmt, check_status))) {
LOG_WARN("failed to check select item has subquery", K(ret));
} else if (!check_status) {
can_be = false;
} else if (view_stmt->is_contains_assignment() || select_stmt->is_contains_assignment()) {
can_be = false;
} else if (OB_FAIL(is_select_item_same(select_stmt, view_stmt, check_status, select_offset, const_select_items))) {
@ -358,6 +362,58 @@ int ObTransformQueryPushDown::check_select_item_push_down(ObSelectStmt* select_s
return ret;
}
int ObTransformQueryPushDown::check_select_item_subquery(ObSelectStmt &select_stmt,
ObSelectStmt &view,
bool &can_be)
{
int ret = OB_SUCCESS;
can_be = true;
ObSEArray<ObRawExpr*, 4> column_exprs_from_subquery;
ObRawExpr *expr = NULL;
TableItem *table = NULL;
ObSqlBitSet<> table_set;
if (OB_UNLIKELY(1 != select_stmt.get_table_items().count())
|| OB_ISNULL(table = select_stmt.get_table_item(0))) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("unexpect select stmt", K(ret), K(select_stmt.get_from_item_size()), K(table));
}
for (int64_t i = 0; OB_SUCC(ret) && i < view.get_select_item_size(); ++i) {
if (OB_ISNULL(expr = view.get_select_item(i).expr_)) {
ret = OB_ERR_UNEXPECTED;
LOG_WARN("unexpect null expr", K(ret));
} else if (!expr->has_flag(CNT_SUB_QUERY)) {
/* do nothing */
} else if (OB_ISNULL(expr = select_stmt.get_column_expr_by_id(table->table_id_,
i + OB_APP_MIN_COLUMN_ID))) {
/* do nothing */
} else if (OB_FAIL(column_exprs_from_subquery.push_back(expr))) {
LOG_WARN("failed to push back column expr", K(ret));
}
}
if (OB_FAIL(ret)) {
} else if (column_exprs_from_subquery.empty()) {
/* do nothing */
} else if (OB_FAIL(select_stmt.get_table_rel_ids(*table, table_set))) {
LOG_WARN("failed to get rel ids", K(ret));
} else {
ObIArray<ObQueryRefRawExpr*> &subquery_exprs = select_stmt.get_subquery_exprs();
ObSEArray<ObDMLStmt *, 4> ignore_stmts;
ObSEArray<ObRawExpr*, 4> column_exprs;
for (int64_t i = 0; OB_SUCC(ret) && can_be && i < subquery_exprs.count(); ++i) {
column_exprs.reuse();
if(OB_FAIL(ObTransformUtils::extract_column_exprs(subquery_exprs.at(i),
select_stmt.get_current_level(),
table_set, ignore_stmts,
column_exprs))) {
LOG_WARN("extract column exprs failed", K(ret));
} else if (ObOptimizerUtil::overlap(column_exprs, column_exprs_from_subquery)) {
can_be = false;
}
}
}
return ret;
}
int ObTransformQueryPushDown::check_where_condition_push_down(
ObSelectStmt* select_stmt, ObSelectStmt* view_stmt, bool& transform_having, bool& can_be)
{