mysql 语句求优化

[起名不容易]

SELECT COUNT(DISTINCT cookieid) cook,
(SELECT COUNT(DISTINCT cookieid) FROM datasources
WHERE DATE_FORMAT(createtime,'%Y-%m-%d')=DATE_FORMAT(d.createtime,'%Y-%m-%d')
AND cookieid NOT IN
(SELECT cookieid FROM datasources WHERE DATE_FORMAT(createtime,'%Y-%m-%d') < DATE_FORMAT(d.createtime,'%Y-%m-%d'))
)ck
FROM datasources d
GROUP BY DATE_FORMAT(d.createtime,'%d')

[LongRui888]

这个： WHERE DATE_FORMAT(createtime,'%Y-%m-%d') < DATE_FORMAT(d.createtime,'%Y-%m-%d') 别这么写，不然用不上索引的。 WHERE createtime< DATE_FORMAT(d.createtime,'%Y-%m-%d')