我该如何选择SQL上的未阻止注释

Question

我应该如何选择未阻止的评论

例如，我们有这些表和记录，是否可以显示一个用户想要查看的评论列表？

这样的事情：userId2（B）可以看到的评论列表

结果必须是：

{ 2, "Comment 3" & 2, "Comment 4" & 4, "Comment 6" }

这是我错误的选择：

SELECT        
    Comments.Comment, Comments.UserId
FROM            
    Users 
INNER JOIN
    Comments ON Users.UserId = Comments.UserId 
INNER JOIN
    Block ON Users.UserId = Block.BlockerId AND Users.UserId = Block.BlockedId
WHERE        
    (Block.BlockerId <> 2) 
    AND (Block.BlockedId <> 2) 
    AND (Users.UserId = 2)

此处还有我的示例数据库＆＃34; testDB.bak＆＃34;的链接：

Click here to download(File size:200KB)

感谢您帮助我

Answer 1

如果我理解规则，这似乎应该有效：

SELECT * FROM Comments WHERE UserId NOT IN (SELECT BlockedId FROM Block WHERE BlockerId=2)

Answer 2

我认为你正在寻找这样的东西：

func updatePickValue(heroes: [Hero], withValue: Int, forSynergy: String) {
    let filteredResults = heroes.filter({$0.synergy.contains(forSynergy)})
    for hero in filteredResults {
        hero.pickValue = withValue
    }

}