I am trying to move my cache into ndb but when I use the ndb engine the query time is 4 min versus myisam which is 7 seconds. This is due to the fact it is doing a full table scan on ndb and an index on myisam. I was hoping someone could help me fix this or at least explain why this is happening. I have included the select statements , the select statement and the explain select for both the ndb and the myisam.
Cache database (ndb) Select distinct t0.panelId from cache1 t0, cache2 t1 where t0.panelid=t1.panelid; (282.54 s) CREATE TABLE `panel`.`cache1` ( `panelId` int(11) DEFAULT NULL, KEY `panelid` (`panelId`) ) ENGINE=ndbcluster DEFAULT CHARSET=utf8; CREATE TABLE `panel`.`cache2` ( `panelId` int(11) DEFAULT NULL, KEY `panelid` (`panelId`) ) ENGINE=ndbcluster DEFAULT CHARSET=utf8; Explain select distinct t0.panelId from cache1 t0, cache2 t1 where t0.panelid=t1.panelid; +----+-------------+-------+------+---------------+---------+---------+- -----------------+--------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+------+---------------+---------+---------+- -----------------+--------+-------------+ | 1 | SIMPLE | t0 | ALL | panelid | NULL | NULL | NULL | 534063 | | | 1 | SIMPLE | t1 | ref | panelid | panelid | 5 | cache.t0.panelId | 1 | Using where | +----+-------------+-------+------+---------------+---------+---------+- -----------------+--------+-------------+ Panel database (myisam) select distinct t0.panelId from cache3 t0, cache4 t1 where t0.panelid=t1.panelid; (6.5 s) CREATE TABLE `panel`.`cache3` ( `panelId` int(11) DEFAULT NULL, KEY `panelid` (`panelId`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; CREATE TABLE `panel`.`cache4` ( `panelId` int(11) DEFAULT NULL, KEY `panelid` (`panelId`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; explain select distinct t0.panelId from cache3 t0, cache4 t1 where t0.panelid=t1.panelid; +----+-------------+-------+-------+---------------+---------+---------+ ------------------+--------+------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+---------------+---------+---------+ ------------------+--------+------------------------------------+ | 1 | SIMPLE | t0 | index | panelid | panelid | 5 | NULL | 534053 | Using index; Using temporary | | 1 | SIMPLE | t1 | ref | panelid | panelid | 5 | panel.t0.panelId | 1 | Using where; Using index; Distinct | +----+-------------+-------+-------+---------------+---------+---------+ ------------------+--------+------------------------------------+ Thanks Joshua Gordon
