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MySQL Delete

发表于 2020-01-08 更新于 2023-03-01 分类于 MySQL
本文字数： 167 阅读时长 ≈ 1 分钟

别名

delete使用别名的时候，要在delete和from间加上删除表的别名，这样才是正确的写法。

delete p,r from t_satisfaction_followup_patients p,t_hospital_followup_record r 
where p.plan_id = '7421aed79a77494d8b2f54c33f62dd2c'
AND r.plan_id = '7421aed79a77494d8b2f54c33f62dd2c'
AND r.submit_status = 0
AND p.id = r.relation_id

多表删除

您可以在DELETE语句中指定多个表，以根据WHERE子句中的条件从一个或多个表中删除行。不能使用ORDER BY或LIMIT在多台 DELETE。

1 2	DELETE t1, t2 FROM t1 INNER JOIN t2 INNER JOIN t3 WHERE t1.id=t2.id AND t2.id=t3.id;

1 2	DELETE t1, t2 FROM t1 INNER JOIN t2 INNER JOIN t3 WHERE t1.id=t2.id AND t2.id=t3.id;

1	DELETE t1 FROM t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t2.id IS NULL;