目录
- mysql delete的语法别名问题
- mysql delete 语句中使用别名 alias
mysql delete的语法别名问题
首先确认，mysql中的delete语句是支持别名的；
在自己书写delete语法时候，语句如下：
delete from tableA a where a.c_pk_id = '123'
但是会报一个别名使用错误，如下：
[Err] 1064 – You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘q
WHERE
q.C_PLY_NO = ‘1100107000404000220150000001’
AND q.N_EDR_PRJ_NO = ‘1” at line 3
通过查询资料得知，mysql的delete的语法有些特殊，如下：
delete a from tableA a where a.c_pk_id = '123'
成功删除！！！
比较之后可知道，delete语句在用别名的时候要多写一个别名在delete后边
mysql delete 语句中使用别名 alias
语法：
delete <alias> from <table> <alias> where <alias>.<field>...
别名必需在 delete之后出一次。
多表间删除语法：
DELETE t1, t2 FROM t1 INNER JOIN t2 INNER JOIN t3 WHERE t1.id=t2.id AND t2.id=t3.id;
Or：
DELETE FROM t1, t2 USING t1 INNER JOIN t2 INNER JOIN t3 WHERE t1.id=t2.id AND t2.id=t3.id;
LEFT JOIN：
DELETE t1 FROM t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t2.id IS NULL;
以上为个人经验，希望能给大家一个参考，也希望大家多多支持NICE源码。
