我在mySQL中有一个基本的follower/following表,看起来像这样。
id user_id follower_id
1 userA userB
2 userC userA
3 userA userC
4 userB userC
5 userB userA
我检查了这些主题,但没有找到我需要的
数据库设计'followers'和& # 39;追随者# 39;?
SQL Following and follower
我需要的是这样一个系统:
假设我们是userB(后面跟着userA,后面跟着userC和userA)
我想返回一个包含这个follower/following状态的结果。例如userB:
id followedBy areWeFollowing
1 userA 1
2 userC 0
谢谢你的帮助!
斯巴达用这个查询来查找如果你关注谁,那么也关注你。
SELECT ff1.follower_id as followedBy,
(
select count(follower_id)
from follower_following as ff2
where ff2.user_id = ff1.follower_id
and ff2.follower_id = ff1.user_id
) as areWeFollowing
FROM follower_following as ff1
where user_id = 'userB';