[求助] 关于 mysql 子查询和 IN 的问题

```
... IN (SELECT `id` FROM `member` WHERE `friendsid` = ( SELECT `id` FROM `member` WHERE `id` = '1' ))...
```

这样的语句，出来的结果是 IN(2,3,4)
怎么把子查询最里面的 ID 为 1 的也添加到 IN 查询里去
比如 IN(1,2,3,4)这样

select

Member

Where

from

3 replies • 2019-12-27 23:27:03 +08:00

0x663

Dec 27, 2019

IN (1,SELECT `id` FROM `member` WHERE `friendsid` = ( SELECT `id` FROM `member` WHERE `id` = '1' ))

0x663

Dec 27, 2019

上边是开玩笑的
```sql
IN (1,SELECT `id` FROM `member` WHERE `friendsid` = (
SELECT `id` FROM `member` WHERE `id` = '1' )
union
select 1 as id
)
```

kukala

Dec 27, 2019

@liushaokang 感谢回复！原来用 union 就行了