SQL INNER JOIN + SELECT NOT EXIST ID's

Question

我有三张桌子：

表一：用户

表二：角色

表三：UserInRoles

• 用户

UserID                                |  FullName
--------------------------------------------------
07DCEE4A-6598-42E1-95C6-0390FF8BB534  | John Doe

• 角色

RoleID
---------------------------------------
E5C46F8E-EE6A-4052-AABA-08184E5F0158

• UserInRoles

UserID                               | RoleID
---------------------------------------------------------------------------
07DCEE4A-6598-42E1-95C6-0390FF8BB534 | E5C46F8E-EE6A-4052-AABA-08184E5F0158

我需要从表UsersID中选择不在表UserInRoles中的所有Users

我试过：

SELECT DISTINCT Users.UserId, Users.FullName 
FROM Users 
INNER JOIN UserInRoles 
ON Users.UserId <> UserInRoles.UserId

Answer 1

思考NOT IN或NOT EXISTS：

select u.*
from users u
where not exists (select 1 from UserInRules ur where u.UserId = ur.UserId);

Answer 2

要从表Users中选择不在表UserInRoles中的所有UsersID，只需使用not in

select distinct * from users where userid not in
(select userid from UserInroles)