Question

sql语句，删除A表中每个字段都重复的记录，应该怎么写?

重复的只保留一条

Answer 1

delete from tablename where rowid not in(select max(rowid) from test group by col1,col2,col3,...);

上面的都不对，这个语句我亲自试过的

Answer 2

最简单方法
select distinct * into b from a
delete from a
insert into a select * from b
drop table b

Answer 3

--说明：删除重复记录
Delete from tablename where id not in (select max(id) from tablename group by col1,col2,...)

Answer 4

这种重复记录要全部删除，还是要保留一条?