SQL计数where子句

Question

我有以下SQL语句：

 SELECT        [l.LeagueId] AS LeagueId, [l.LeagueName] AS NAME, [lp.PositionId]
 FROM            (Leagues l INNER JOIN
                     Lineups lp ON l.LeagueId = lp.LeagueId)
 WHERE        (lp.PositionId = 1) OR
                     (lp.PositionId = 3) OR
                     (lp.PositionId = 2)

我真正需要的是让行，其中位置的数量比数。是这样的：

 SELECT        [l.LeagueId] AS LeagueId, [l.LeagueName] AS NAME, [lp.PositionId]
 FROM            (Leagues l INNER JOIN
                     Lineups lp ON l.LeagueId = lp.LeagueId)
 WHERE        Count(lp.PositionId = 1) > 2 OR
                     Count(lp.PositionId = 3) > 6 OR
                     Count(lp.PositionId = 2) > 3

有没有办法在SQL做到这一点？

Answer 1

这个怎么样？

SELECT        [l.LeagueId] AS LeagueId, [l.LeagueName] AS NAME
 FROM            (Leagues l INNER JOIN
                     Lineups lp ON l.LeagueId = lp.LeagueId)
 GROUP BY [l.LeagueId], [l.LeagueName]
 HAVING        SUM(CASE WHEN lp.PositionId = 1 THEN 1 ELSE 0 END) > 2 OR
                     SUM(CASE WHEN lp.PositionId = 3 THEN 1 ELSE 0 END) > 6 OR
                     SUM(CASE WHEN lp.PositionId = 2 THEN 1 ELSE 0 END) > 3

Answer 2

HAVING就是你要找的关键字：

SELECT        [l.LeagueId] AS LeagueId, [l.LeagueName] AS NAME, [lp.PositionId]
FROM            (Leagues l INNER JOIN
                     Lineups lp ON l.LeagueId = lp.LeagueId)
GROUP BY lp.PositionId, l.LeagueName
HAVING lp.PositionId = 1 AND COUNT(*) > 2 
       OR lp.PositionId = 2 AND COUNT(*) > 3 
       OR lp.PositionId = 3 AND COUNT(*) > 6