MySQL的：與條件

Question

用戶ID的收益名單上有表「battle_user」管理戰役和用戶表

表「battle_user」結構之間的關係：

battle_id  user_id 
1111   1 
1111   2 
22    1 
22    3 
3    2 
3    3 

如何reutrn「USER_ID」名單與特定的用戶， 紛紛上陣，如用戶ID的退貨單有USER_ID戰鬥= 1

的結果應該是：

user_id 
2 
3 

Answer 1

我寫了一個查詢：

select distinct(b.user_id) 
from battle_user b 
inner join battle_user b2 on b.battle_id = b2.battle_id and b2.user_id = 10 
where b.user_id <> 10 

Answer 2

你可以做

select 
b1.user_id from battle_user b1 
where b1.user_id<>1 
and exists ( 
    select 1 from battle_user b2 
    where 
    b2.battle_id = b1.battle_id 
    and b2.user_id = 1 
); 

Answer 3

SELECT distinct(user_id) FROM battle_user 
WHERE battle_id IN (select battle_id from battle_user where user_id = 1) and user_id <> 1