Hi Sergej, Thank you for this update. I'm still curious: does CONNECT read the rows several times? If so, is there a way to avoid this until the bug is solved?
Regards, Federico -------------------------------------------- El lun, 12/5/14, Sergei Golubchik <s...@mariadb.org> escribió: Asunto: Re: [Maria-discuss] EXPLAIN and CONNECT Para: "Federico Razzoli" <federico_...@yahoo.it> CC: maria-discuss@lists.launchpad.net Fecha: lunes, 12 de mayo, 2014 15:40 Hi, Federico! On Mar 27, Federico Razzoli wrote: > Hi Sergei > > You can repeat this very easily: > > MariaDB [test]> CREATE TABLE t_connect (c INT PRIMARY KEY) ENGINE=CONNECT TABLE_TYPE=CSV; > Query OK, 0 rows affected, 1 warning (0.11 sec) > > Warning (Code 1105): No file name. Table will use t_connect.csv > MariaDB [test]> INSERT INTO t_connect VALUES (1),(2);Query OK, 2 rows affected (0.00 sec) > Records: 2 Duplicates: 0 Warnings: 0 > > MariaDB [test]> EXPLAIN SELECT MAX(c) FROM t_connect; > +------+-------------+-----------+------+---------------+------+---------+------+------+-------+ > | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | > +------+-------------+-----------+------+---------------+------+---------+------+------+-------+ > | 1 | SIMPLE | t_connect | ALL | NULL | NULL | NULL | NULL | 4 | | > +------+-------------+-----------+------+---------------+------+---------+------+------+-------+ > 1 row in set (0.00 sec) > > But adding more rows, the difference between the rows value and the reality becomes big. Thanks, I've reported it as https://mariadb.atlassian.net/browse/MDEV-6232 I tried to repeat it earlier, but then it uncovered other bugs in the CONNECT indexes, they're fixed now. Your original query gets "Table was optimized away", so I have to modified it a bit for the bug report. Regards, Sergei _______________________________________________ Mailing list: https://launchpad.net/~maria-discuss Post to : maria-discuss@lists.launchpad.net Unsubscribe : https://launchpad.net/~maria-discuss More help : https://help.launchpad.net/ListHelp
