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  • mysql关联删除

    1、从数据表t1中把那些id值在数据表t2里有匹配的记录全删除掉1  

     DELETE t1 FROM t1,t2 WHERE t1.id=t2.id 
    DELETE FROM t1 USING t1,t2 WHERE t1.id=t2.id

    2、从数据表t1里在数据表t2里没有匹配的记录查找出来并删除掉1  

    DELETE t1 FROM t1 LEFT JOIN T2 ON t1.id=t2.id WHERE t2.id IS NULL 
    DELETE FROM t1,USING t1 LEFT JOIN T2 ON t1.id=t2.id WHERE t2.id IS NULL

    3.从两个表中找出相同记录的数据并把两个表中的数据都删除掉1

    DELETE t1,t2 from t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t1.id=25

    注意此处的delete t1,t2 from 中的t1,t2不能是别名

    delete t1,t2 from table_name as t1 left join table2_name as t2 on t1.id=t2.id where table_name.id=25(MYSQL 版本不小于5.0在5.0中是可以的)
    
    delete table_name,table2_name from table_name as t1 left join table2_name as t2 on t1.id=t2.id where table_name.id=25
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  • 原文地址:https://www.cnblogs.com/yin-fei/p/10881264.html
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