优化前
SELECT
`mdz_anchor`.*
FROM
`mdz_anchor`
WHERE id not in ( select anchor_id from `activity_center`.`mdz_live` where mdz_live.status=0 AND STATUS = 0
AND company_id =2 )
AND STATUS = 0
AND company_id =2

优化后
SELECT
`mdz_anchor`.*
FROM
`mdz_anchor`
LEFT JOIN `activity_center`.`mdz_live` ON mdz_live.anchor_id = mdz_anchor.id
WHERE
mdz_live.anchor_id IS NULL
AND mdz_anchor.STATUS = 0
AND mdz_anchor.company_id =2

本文介绍了Mysql中使用not in语句的一种优化方法:通过将not in转换为left join...并结合具体案例展示了如何进行优化,提高了查询效率。
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