Question

我有一个表可以有ip_address的多个记录。但是，我想返回canceled=0 的行，如果存在ip_address的多个记录，否则请获取canceled=1

的第一行

id  ip_address  username  canceled
0   10.10.10.1  john      0
1   10.10.10.1  johnny    1
2   10.10.10.1  quincy    1
3   10.10.10.2  bob       1
4   10.10.10.3  kristin   0

示例返回SELECT ip_address,username ....的结果集：

10.10.10.1  john
10.10.10.2  bob
10.10.10.3  kristin

如果有任何相关性，请使用SQLAlchemy / Sqlite。

SELECT 
  b.id,
  a.ip_address,
  b.username,
  b.canceled
FROM (
  select distinct(ip_address) from mytable order by canceled) a,
  mytable b
WHERE
  b.ip_address=a.ip_address;

但是这会为＆＃34; ip_address＆＃34;

返回多个定义

Answer 1

正确的查询似乎是：

SELECT b.id,a.ip_address,b.username,b.canceled FROM (select distinct(ip_address) from mytable order by canceled) a, mytable b WHERE b.ip_address=a.ip_address GROUP BY b.ip_address

Answer 2

假设取消是一个int，这应该可行。

select *from #temp order by canceled
with cte as 
(
select ip_address,username,canceled,ROW_NUMBER() over(partition by  ip_address order by canceled) as rn from #temp
)
select *from cte where rn=1

SQL查询以获取具有基于行值的首选项的行

2 个答案: