From 39f9a3ffd0de8828be2a43b9674a19fa58c52f98 Mon Sep 17 00:00:00 2001 From: Alexey Kopytov Date: Fri, 6 Nov 2009 09:44:01 +0300 Subject: Bug #48475: DISTINCT is ignored with GROUP BY WITH ROLLUP and only const tables The problem was caused by two shortcuts in the optimizer that are inapplicable in the ROLLUP case. Normally in a case when only const tables are involved in a query, DISTINCT clause can be safely optimized away since there may be only one row produced by the join. Similarly, we don't need to create a temporary table to resolve DISTINCT/GROUP BY/ORDER BY. Both of these are inapplicable when the WITH ROLLUP modifier is present. Fixed by disabling the said optimizations for the WITH ROLLUP case. mysql-test/r/olap.result: Added a test case for bug #48475. mysql-test/t/olap.test: Added a test case for bug #48475. sql/sql_select.cc: Disabled const-only table optimizations for the WITH ROLLUP case. --- mysql-test/t/olap.test | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'mysql-test/t/olap.test') diff --git a/mysql-test/t/olap.test b/mysql-test/t/olap.test index 8f672af40a3..fec5df1a1c7 100644 --- a/mysql-test/t/olap.test +++ b/mysql-test/t/olap.test @@ -390,4 +390,17 @@ SELECT DISTINCT b FROM t1, t2 GROUP BY a, b WITH ROLLUP; DROP TABLE t1, t2; +--echo # +--echo # Bug #48475: DISTINCT is ignored with GROUP BY WITH ROLLUP +--echo # and only const tables + +CREATE TABLE t1 (a INT); +CREATE TABLE t2 (b INT); +INSERT INTO t1 VALUES (1); +INSERT INTO t2 VALUES (1); + +SELECT DISTINCT b FROM t1, t2 GROUP BY a, b WITH ROLLUP; + +DROP TABLE t1, t2; + --echo End of 5.0 tests -- cgit v1.2.1