如何在SQL中合并计数值

Question

我正在尝试将桌队的所有城市值更新为：“城市” +“＃p” +“球员人数” +“ g” +“前进目标数”（例如“东京＃p25 g74”）。

我试图做到这一点，并有这两个查询。 一个用于获取玩家数量，一个用于获取目标数量。

查询玩家人数：

select  t.city + '#p' + CONVERT(varchar(10), count(pt.playerId)) + '#g' 
from    team        t, 
        player_team pt 
where   pt.teamID = t.teamID 
group By t.teamId,t.city

查询目标数量：

select  count(*) totalgoals,
        pt.teamID 
from    goals       g, 
        player_team pt 
where   g.playerId = pt.playerId 
group by pt.teamID

我无法将这两个因素合并。 请帮我...

还有我的表层次结构和字段，如下所示

player 
(
    playerID        int, 
    firstName       nvarchar(25), 
    lastName        nvarchar(25), 
    nationality     varchar(25), 
    birthDate       smalldatetime, 
    age             smallint, 
    position        varchar(25)
)

team 
(
    teamID  int,
    name    nvarchar(50), 
    city    nvarchar(25)
)

player_team 
(
    playerID    int, 
    teamID      int, 
    season      varchar(5)
)

match 
(
    matchID         int,
    homeTeamID      int, 
    visitingTeamID  int, 
    dateOfMatch     smalldatetime, 
    week            tinyint
)

goals 
(
    matchID     int, 
    playerID    int, 
    isOwnGoal   bit, 
    minute      tinyint
)

编辑：使用下面给出的选择查询效果很好，并给了我正确的结果。但是我怎么用这个多条记录更新表？ 当我尝试将其作为子查询更新到update语句时，它给了我编译错误并抱怨多记录...

错误：子查询返回了多个值。 当子查询遵循=，！=，<，<=，>，> =或将子查询用作表达式时，不允许这样做。

Answer 1

假设您的2个查询产生了所需的结果，请尝试将它们与outer join和子查询组合：

select  pt.teamId, 
  t.city + ' #p' + CONVERT(varchar(10), count(pt.playerId)) 
         + ' g' + CONVERT(varchar(10), t2.totalgoals)
from    team        t
  inner join player_team pt on pt.teamID = t.teamID 
  left join (
      select  count(*) totalgoals,
              pt.teamID 
      from    goals       g inner join player_team pt on g.playerId = pt.playerId 
      group by pt.teamID
    ) t2 on t.teamid = t2.teamid 
group By pt.teamId,t.city,t2.totalgoals

• SQL小提琴演示

Answer 2

最简单的方法可能是使用相关子查询来查找每个团队的值：

SELECT t.city || ' #p' ||
       CONVERT(varchar(10), (SELECT count(*)
                             FROM player_team
                             WHERE teamId = t.teamId))
       || ' #g ' ||
       CONVERT(varchar(10), (SELECT count(*)
                             FROM goals
                             JOIN player_team USING (playerId)
                             WHERE teamId = t.teamId))
FROM team t

Answer 3

尝试这个：

SELECT a.city '#p' + CONVERT(varchar(10), a.playerCount) + '#g' + CONVERT(varchar(10), b.totalgoals) 
FROM (SELECT t.teamId, t.city, count(pt.playerId) as playerCount
      FROM team t JOIN player_team pt on (t.teamID = pt.teamID)
      GROUP BY t.teamId, t.city)a JOIN 
      (SELECT pt.teamId, count(*) as totalgoals,
      FROM goals g JOIN player_team pt on (g.playerId = pt.playerId) 
      GROUP BY pt.teamId) b ON (a.teamId = b.teamId)