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php mysql update遇到unique索引则删除本纪录

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Jun 06, 2016 am 09:39 AM

mysqlphp索引

图片说明

uid和book_id有联合unqiue索引，即一个人只能有一本书

需求：更新11和14行，使uid=1005，若产生unique索引冲突（13和14行），则删除待更新的行（14行）

我能想到的办法是，先select待更新行并保存，同时删除(delete)这些行,再用insert IGNORE 插入。

这样太笨了，有没有操作mysql的方法，比如触发器什么的，或者更高效的，求教！！

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