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mysql批量去除重复内容的办法

1、创建临时表。其中下面的 word 是指重复字段，自己替换

create table tmp_word as (select word from v9_keylink group by word having count(word))

create table tmp_id as (select min(keylinkid) from v9_keylink group by word having count(word))

2、创建两个表的索引，否则第三步的执行速度会让你自杀

create index index_word on tmp_word (word);

create index index_id on tmp_id (keylinkid);

3、执行查询删除语句

delete from v9_keylink where keylinkid not in (select keylinkid from tmp_id) and word in (select word from tmp_word)