一张person表，有id和name的两个字段，id是唯一的不允许重复，id相同则认为是重复的记录。
select id from group by id having count(*) > 1
查找表中多余的重复记录，重复记录是根据单个字段（Id）来判断
select * from 表 where Id in (select Id from 表 group byId having count(Id) > 1)
删除表中多余的重复记录，重复记录是根据单个字段（Id）来判断，只留有rowid最小的记录
DELETE from 表 WHERE (id) IN ( SELECT id FROM 表 GROUP BY id HAVING COUNT(id) > 1) AND ROWID NOT IN (SELECT MIN(ROWID) FROM 表 GROUP BY id HAVING COUNT(*) >1);
查找表中多余的重复记录（多个字段）
select
* from 表 a where (a.Id,a.seq) in(select Id,seq from 表 group by Id,seq having
count(*) > 1)
删除表中多余的重复记录（多个字段），只留有rowid最小的记录
delete
from 表 a where (a.Id,a.seq) in (select Id,seq from 表 group by Id,seq having
count(
) > 1) and rowid not in (select min(rowid) from 表 group by Id,seq
having count(
)>1)
查找表中多余的重复记录（多个字段），不包含rowid最小的记录
select
* from 表 a where (a.Id,a.seq) in (select Id,seq from 表 group by Id,seq having
count(
) > 1) and rowid not in (select min(rowid) from 表 group by Id,seq
having count(
)>1)
