sql多条重复数据取唯一值 Mysql如何去掉数据库中的重复记录？

Mysql如何去掉数据库中的重复记录？很简单 通过id删除DELETE FROMtable_name AS ta WHEREta.唯一键 <> (SELECTt.maxid FROM( SEL

Mysql如何去掉数据库中的重复记录？

很简单 通过id删除

DELETE

FROM

table_name AS ta

WHERE

ta.唯一键 <> (

SELECT

t.maxid

FROM

( SELECT max( tb.唯一键 ) AS maxid FROM table_name AS tb WHERE ta.判断重复的列 = tb.判断重复的列 ) t

)

Mysql数据库中多条重复数据，如何只删除一条？

列出要保留的记录ID，可以把这个结果写到一个临时表t1中： SELECT MAX(id) AS max_id FROM pedigree GROUP BY number然后：DELETE FROM pedigree WHERE id NOT IN (SELECT id FROM t1)也就是：delete from pedigree where id not in(select * from pedigree where group by number)。pedigree where id not in(select max(id) from pedigree where group by number having count(id) > 0) 查询结果是否符合删除要求！