我在mysql中有这个查询,我想索引,什么是最好的索引组成?索引mysql查询
SELECT cometchat.id, cometchat.from, cometchat.to, cometchat.message, cometchat.sent, cometchat.read, cometchat.direction
FROM cometchat
WHERE (
(
cometchat.to = '30411'
AND cometchat.direction <>2
)
OR (
cometchat.from = '30411'
AND cometchat.direction <>1
)
)
我已经试过这些指标,但他们没有工作:
ALTER TABLE `cometchat` ADD INDEX ( `from`,`to`,`direction`)
ALTER TABLE `cometchat` ADD INDEX ( `from`,`to`)
ALTER TABLE `cometchat` ADD INDEX ( `to`,`direction`)
ALTER TABLE `cometchat` ADD INDEX ( `from`,`direction`)
任何帮助将非常感激。
该查询的解释计划是什么? – doublesharp