关注被关注表设计-UserFollowMapping

-- ----------------------------
-- Table structure for UserFollowMapping
-- ----------------------------
DROP TABLE [dbo].[UserFollowMapping]
GO
CREATE TABLE [dbo].[UserFollowMapping] (
[UserId] bigint NOT NULL ,
[FollowUserID] bigint NOT NULL 
)


GO

-- ----------------------------
-- Records of UserFollowMapping
-- ----------------------------
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'1', N'10')
GO
GO
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'10', N'1')
GO
GO
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'11', N'12')
GO
GO
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'13', N'14')
GO
GO
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'15', N'16')
GO
GO
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'16', N'15')
GO
GO
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'16', N'1')
GO
GO
INSERT INTO [dbo].[UserFollowMapping] ([UserId], [FollowUserID]) VALUES (N'1', N'16')
GO
GO

-------------------------------------------------------
select * from dbo.UserFollowMapping

--  1  的 粉丝列表
select * from dbo.UserFollowMapping where UserId=1
--  1  的关注列表
select * from dbo.UserFollowMapping where FollowUserID=1

-- 1 的 互粉列表 （双向的关注列表 取交集）
select UserId,FollowUserID from dbo.UserFollowMapping where UserId=1
INTERSECT 
select FollowUserID,UserId from dbo.UserFollowMapping where FollowUserID=1