Commit 791deb8b authored by istruewing@stella.local's avatar istruewing@stella.local

Merge stella.local:/home2/mydev/mysql-5.0-axmrg

into  stella.local:/home2/mydev/mysql-5.1-axmrg
parents 3707119e fc888bc9
...@@ -13,20 +13,20 @@ CREATE TABLE t2 (p POINT, INDEX(p)); ...@@ -13,20 +13,20 @@ CREATE TABLE t2 (p POINT, INDEX(p));
INSERT INTO t1 VALUES (POINTFROMTEXT('POINT(1 2)')); INSERT INTO t1 VALUES (POINTFROMTEXT('POINT(1 2)'));
INSERT INTO t2 VALUES (POINTFROMTEXT('POINT(1 2)')); INSERT INTO t2 VALUES (POINTFROMTEXT('POINT(1 2)'));
-- no index, returns 1 as expected # no index, returns 1 as expected
SELECT COUNT(*) FROM t1 WHERE p=POINTFROMTEXT('POINT(1 2)'); SELECT COUNT(*) FROM t1 WHERE p=POINTFROMTEXT('POINT(1 2)');
-- with index, returns 1 as expected # with index, returns 1 as expected
-- EXPLAIN shows that the index is not used though # EXPLAIN shows that the index is not used though
-- due to the "most rows covered anyway, so a scan is more effective" rule # due to the "most rows covered anyway, so a scan is more effective" rule
EXPLAIN EXPLAIN
SELECT COUNT(*) FROM t2 WHERE p=POINTFROMTEXT('POINT(1 2)'); SELECT COUNT(*) FROM t2 WHERE p=POINTFROMTEXT('POINT(1 2)');
SELECT COUNT(*) FROM t2 WHERE p=POINTFROMTEXT('POINT(1 2)'); SELECT COUNT(*) FROM t2 WHERE p=POINTFROMTEXT('POINT(1 2)');
-- adding another row to the table so that # adding another row to the table so that
-- the "most rows covered" rule doesn't kick in anymore # the "most rows covered" rule doesn't kick in anymore
-- now EXPLAIN shows the index used on the table # now EXPLAIN shows the index used on the table
# and we're getting the wrong result again
INSERT INTO t1 VALUES (POINTFROMTEXT('POINT(1 2)')); INSERT INTO t1 VALUES (POINTFROMTEXT('POINT(1 2)'));
INSERT INTO t2 VALUES (POINTFROMTEXT('POINT(1 2)')); INSERT INTO t2 VALUES (POINTFROMTEXT('POINT(1 2)'));
EXPLAIN EXPLAIN
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment