Question

SELECT * FROM User
INNER JOIN BlockUser ON BlockUser.userId='1' and User.userId != BlockUser.blockID

我有两个表格是“用户”表和 BlockUser 表。

我需要从用户表中选择除特定用户阻止的用户

之外的所有用户

用户表

userID  userName  nickName
1       abc       abc
2       adc       adc
3       dc        dc
4       xyz       xyz
5       qwe       qwe

BlockUser

_Id  userId  blockID
1      1       2
2      1       3

结果

userID  userName  nickName
4       xyz       xyz
5       qwe       qwe

请帮我纠正我的Sql查询。

Answer 1

试试这个：

DECLARE @blocker int = 1
SELECT * FROM [User]
WHERE [User].userID NOT IN (SELECT BlockUser.blockID FROM BlockUser WHERE BlockUser.blockID = [User].userID AND BlockUser.userID = @blocker)
AND userID <> @blocker

http://sqlfiddle.com/#!3/a7012/14

错误也是SQL关键字，它是表的名称，更改表用户的名称或使用括号如图所示。

还有其他解决方案（来自其他用户但已删除）：

select u.*
from [User] u
left join BlockUser bu on bu.blockID = u.userID
                      and bu.userId = 1
where bu.userID is null
      and u.userID <> 1;

select * from [user]
where userID <> 1
and userID not in 
  (select blockID from BlockUser 
   where userID = 1);

编辑1：修正查询
编辑2：钉它 - 不是:)
编辑3：考虑使用变量
从结果中删除阻止程序 编辑4：添加了其他解决方案

Answer 2

您的查询如下：从userID NOT IN的用户中选择userID，userName，nickName（从BlockUser中选择blockID，其中userId = 1）;

Answer 3

将连接类型更改为外连接，然后过滤用户表以获取非空记录。

Answer 4

select * from user 
where userId <> '1'
and userid not in 
  (select blocked from BlockUser.userId 
   where userId = '1')

SQL JOIN-当前用户未阻止的用户选择

4 个答案: