mysqlphp索引
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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