[英]sqlite delete rows group by having more than two rows
我有以下表结构:
sqlite> select * from test;
k1 k2 value
---------- ---------- ----------
1 1 10
1 1 20
1 1 30
1 2 10
在这里,我想删除按 (k1,k2) 分组的多于两行的行。
所以,我想删除前三行 (1,1,10)、(1,1,20) 和 (1,1,30)。
我试过以下:
delete from test where rowid in (select test.rowid from test group by k1,k2 having count(*) > 2);
但是,子查询只给出最后一个 rowid:
sqlite> select test.rowid from test group by k1,k2 having count(*) > 2;
rowid
----------
3
因此,所有三行都没有被删除。 而且,我不能在删除查询中直接使用 group by。
关于如何通过查询实现的任何想法?
您可以使用exists
:
delete from test
where exists (select 1
from test t2
where t2.k1 = test.k1 and t2.k2 = test.k2
group by t2.k1, t2.k2
having count(*) > 2
);
或与元组in
使用:
delete from test
where (k1, k2) in (select t2.k1, t2.k2
from test t2
group by t2.k1, t2.k2
having count(*) > 2
);
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.