在这个查询中,我必须列出一对玩家ID和玩家名称的球员,他们为同一支球队效力。如果一名球员为3支球队效力,则另一支球员必须参加完全相同的3支球队。不能少,不多了。如果两名球员目前不参加任何球队,他们也应该被包括在内。查询应该返回(playerID1,playername1,playerID2,playerName2)而没有重复,例如如果玩家1信息在玩家2之前出现,则不应该有另一个玩家2信息在玩家1之前出现的元组。
例如,如果玩家A为洋基队和红袜队队员比赛,而且队员队员为洋基队队员,红袜队队员和道奇队队员队效力,我就不应该参加比赛。他们都必须为洋基队和红袜队效力,而不是其他人。现在,如果玩家为同一个团队玩游戏,此查询会找到答案。
Tables:
player(playerID: integer, playerName: string)
team(teamID: integer, teamName: string, sport: string)
plays(playerID: integer, teamID: integer)
Example data:
PLAYER
playerID playerName
1 Rondo
2 Allen
3 Pierce
4 Garnett
5 Perkins
TEAM
teamID teamName sport
1 Celtics Basketball
2 Lakers Basketball
3 Patriots Football
4 Red Sox Baseball
5 Bulls Basketball
PLAYS
playerID TeamID
1 1
1 2
1 3
2 1
2 3
3 1
3 3
所以我应该把它作为答案 -
2, Allen, 3, Pierce
4, Garnett, 5, Perkins
2,艾伦,3皮尔斯是一个snwer,因为他们只参加CELTICS和PATRIOTS 4,加内特,5,帕金斯给出了答案,因为两位球员都没有参加任何应该输出的球队。
现在我的查询是
SELECT p1.PLAYERID,
f1.PLAYERNAME,
p2.PLAYERID,
f2.PLAYERNAME
FROM PLAYER f1,
PLAYER f2,
PLAYS p1
FULL OUTER JOIN PLAYS p2
ON p1.PLAYERID < p2.PLAYERID
AND p1.TEAMID = p2.TEAMID
GROUP BY p1.PLAYERID,
f1.PLAYERID,
p2.PLAYERID,
f2.PLAYERID
HAVING Count(p1.PLAYERID) = Count(*)
AND Count(p2.PLAYERID) = Count(*)
AND p1.PLAYERID = f1.PLAYERID
AND p2.PLAYERID = f2.PLAYERID;
我不是百分百肯定,但我认为这可以找到为同一支球队效力的球员,但我想找出那些与上述球队完全相同的球员的球员
我坚持在此之后如何接近它。有关如何解决此问题的任何提示。谢谢你的时间。
答案 0 :(得分:4)
我相信这个查询会做你想要的:
SELECT array_agg(players), player_teams
FROM (
SELECT DISTINCT t1.t1player AS players, t1.player_teams
FROM (
SELECT
p.playerid AS t1id,
concat(p.playerid,':', p.playername, ' ') AS t1player,
array_agg(pl.teamid ORDER BY pl.teamid) AS player_teams
FROM player p
LEFT JOIN plays pl ON p.playerid = pl.playerid
GROUP BY p.playerid, p.playername
) t1
INNER JOIN (
SELECT
p.playerid AS t2id,
array_agg(pl.teamid ORDER BY pl.teamid) AS player_teams
FROM player p
LEFT JOIN plays pl ON p.playerid = pl.playerid
GROUP BY p.playerid, p.playername
) t2 ON t1.player_teams=t2.player_teams AND t1.t1id <> t2.t2id
) innerQuery
GROUP BY player_teams
Result:
PLAYERS PLAYER_TEAMS
2:Allen,3:Pierce 1,3
4:Garnett,5:Perkins
对于plays
中的每个玩家,它使用teamid的team_agg匹配具有完全相同团队配置的玩家。例如,我包含了一个包含团队的专栏,但只要不从group by子句中删除,就可以删除该列,而不会影响结果。
SQL Fiddle example.使用Postgesql 9.2.4进行测试
编辑:修复了重复行的错误。
答案 1 :(得分:1)
似乎OP可能不再感兴趣了,但是如果其他人发现它有用, 这是纯SQL中的查询(对我来说至少;))
SELECT M.p1, pr1.playername, M.p2, pr2.playername FROM player pr1
INNER JOIN player pr2 INNER JOIN
(
SELECT plays1.player p1, plays2.player p2, plays1.team t1 FROM plays plays1
INNER JOIN plays plays2
ON (plays1.player < plays2.player AND plays1.team = plays2.team)
GROUP BY plays1.player, plays2.player HAVING COUNT(*) =
((SELECT COUNT(*) FROM plays plays3 WHERE plays3.player = plays1.player) +
(SELECT COUNT(*) FROM plays plays4 WHERE plays4.player = plays2.player)) /2
) M ON pr1.playerID = M.p1 AND pr2.playerID = M.p2
UNION ALL
SELECT M.pid, M.pname, N.pid2, N.pname2 FROM
(
(SELECT p.playerID pid, p.playerName pname, pl.team FROM player p
LEFT JOIN plays pl ON p.playerId = pl.player WHERE pl.team IS NULL) M
INNER JOIN
(SELECT p.playerID pid2, p.playerName pname2, pl.team FROM player p
LEFT JOIN plays pl ON p.playerId = pl.player WHERE pl.team IS NULL) N
ON (pid < pid2)
)
答案 2 :(得分:1)
没什么大不了的,这是解决方案
with gigo as(select a.playerid as playerid,count(b.teamname) as nteams from player a
full outer join plays c on a.playerid=c.playerid full outer join team b
on b.teamid=c.teamid group by a.playerid)
select array_agg(a.*),g.nteams from player a inner join gigo g on a.playerid=g.playerid
group by g.nteams having count(a.*)>1 order by g.nteams desc
答案 3 :(得分:1)
此解决方案适用于我:
SELECT TMP1. PLAYERID,TMP2.PLAYERID FROM
(
SELECT a.playerid , a.teamid,b.team_sum
FROM plays A
INNER JOIN
(
SELECT PLAYERID,SUM(teamid) AS team_sum
FROM plays
GROUP BY 1
) B
ON a.playerid=b.playerid
) TMP1
INNER JOIN
(
SELECT a.playerid , a.teamid,b.team_sum
FROM plays A
INNER JOIN
(
SELECT PLAYERID,SUM(teamid) AS team_sum
FROM plays
GROUP BY 1
) B
ON a.playerid=b.playerid
)TMP2
ON TMP1.PLAYERID < TMP2.PLAYERID
AND TMP1.TEAMID=TMP2.TEAMID
AND TMP1.TEAM_SUM=TMP2.TEAM_SUM
GROUP BY 1,2
UNION ALL
SELECT n1,n2 FROM
(
SELECT TMP3.PLAYERID AS n1,TMP4.PLAYERID AS n2 FROM
PLAYER TMP3
INNER JOIN PLAYER TMP4
ON TMP3.PLAYERID<TMP4.PLAYERID
WHERE TMP3.PLAYERID NOT IN (SELECT PLAYERID FROM plays )
AND tmp4.playerid NOT IN (SELECT playerid FROM plays)
) TMP5
答案 4 :(得分:0)
我想到了两种可能的解决方案:
你能提供一些样本数据,以便我可以创建一个例子吗?
答案 5 :(得分:0)
看起来你想要的基本数据类型是集合,而不是数组。因此,一个选项可能是使用PL / Python,其代码类似于下面的代码(请参阅本答案的底部,了解可能适用于此目的的函数)。当然,这绝不是一种“纯粹的SQL”方法。
但是坚持使用PostgreSQL(虽然不是标准的SQL),你可能也想使用DISTINCT和array_agg。请注意,以下仅提供符合条件的第一对(原则上可能还有更多)。
WITH teams AS (
SELECT playerID, array_agg(DISTINCT teamID ORDER BY teamID) AS teams
FROM plays
GROUP BY playerID),
teams_w_nulls AS (
SELECT a.playerID, b.teams
FROM player AS a
LEFT JOIN teams AS b
ON a.playerID=b.playerID),
player_sets AS (
SELECT teams, array_agg(DISTINCT playerID ORDER BY playerID) AS players
FROM teams_w_nulls
GROUP BY teams
-- exclude players who are only share a team list with themselves.
HAVING array_length(array_agg(DISTINCT playerID ORDER BY playerID),1)>1)
SELECT a.teams, b.playerID, b.playerName, c.playerID, c.playerName
FROM player_sets AS a
INNER JOIN player AS b
ON a.players[1]=b.playerID
INNER JOIN player AS c
ON a.players[2]=c.playerID;
上面的查询给出了以下输出:
teams | playerid | playername | playerid | playername
-------+----------+------------+----------+------------
{1,3} | 2 | Allen | 3 | Pierce
| 4 | Garnett | 5 | Perkins
(2 rows)
示例PL / Python函数:
CREATE OR REPLACE FUNCTION set(the_list integer[])
RETURNS integer[] AS
$BODY$
return list(set(the_list))
$BODY$
LANGUAGE plpython2u;
CREATE OR REPLACE FUNCTION pairs(a_set integer[])
RETURNS SETOF integer[] AS
$BODY$
def pairs(x):
for i in range(len(x)):
for j in x[i+1:]:
yield [x[i], j]
return list(pairs(a_set))
$BODY$
LANGUAGE plpython2u;
SELECT set(ARRAY[1, 1, 2, 3, 4, 5, 6, 6]);
上面使用这些函数的代码版本(输出类似,但是当给定一组团队有多个时,这种方法会选择所有对):
WITH teams AS (
SELECT playerID, set(array_agg(teamID)) AS teams
FROM plays
GROUP BY playerID),
teams_w_nulls AS (
SELECT a.playerID, b.teams
FROM player AS a
LEFT JOIN teams AS b
ON a.playerID=b.playerID),
player_pairs AS (
SELECT teams, pairs(set(array_agg(playerID))) AS pairs
FROM teams_w_nulls
GROUP BY teams)
-- no need to exclude players who are only share a team
-- list with themselves.
SELECT teams, pairs[1] AS player_1, pairs[2] AS player_2
FROM player_pairs;
答案 6 :(得分:0)
我们根据每位玩家的团队数量和ascii(team_name)+ team_id的总和进行查询,称之为team_value。我们对自己进行相同查询的自连接,其中count和team_values匹配,但id不等于id,这为我们提供了我们想要获取的ID
select * from player where player_id in
(
select set2.player_id orig
from
(select count(*) count,b.player_id , nvl(sum(a.team_id+ascii(team_name)),0) team_value
from plays a, player b , team c
where a.player_id(+)=b.player_id
and a.team_id = c.team_id(+)
group by b.player_id) set1,
(select count(*) count,b.player_id , nvl(sum(a.team_id+ascii(team_name)),0) team_value
from plays a, player b , team c
where a.player_id(+)=b.player_id
and a.team_id = c.team_id(+)
group by b.player_id) set2
where set1.count=set2.count and set1.team_value=set2.team_value
and set1.player_id<>set2.player_id
)
答案 7 :(得分:0)
这是使用UNION和2-3个简单连接的简单查询。 UNION之前的第一个查询包含玩家名称和玩家队伍相同数量的队员相同次数。 UNION之后的第二个查询包含没有为任何球队效力的球员名称和球员。
只需复制粘贴此查询并尝试执行它,您将看到预期的结果。
select playername,c.playerid from
(select a.cnt, a.playerid from
(select count(1) cnt , PLAYERID from plays group by PLAYERID) a ,
(select count(1) cnt , PLAYERID from plays group by PLAYERID) b
where a.cnt=b.cnt
and a.playerid<> b.playerid ) c ,PLAYER d
where c.playerid=d.playerid
UNION
select e.playername,e.playerid
from player e
left outer join plays f on
e.playerid=f.playerid where nvl(teamid,0 )=0
答案 8 :(得分:0)
试试这个: 这里测试是你问题中的PLAYS表。
select group_concat(b.name),a.teams from
(SELECT playerid, group_concat(distinct teamid ORDER BY teamid) AS teams
FROM test
GROUP BY playerid) a, player b
where a.playerid=b.playerid
group by a.teams
union
select group_concat(c.name order by c.playerid),null from player c where c.playerid not in (select playerid from test);
答案 9 :(得分:0)
对于任何感兴趣的人,这个简单的查询对我有用
SELECT UNIQUE PLR1.PID,PLR1.PNAME, PLR2.PID, PLR2.PNAME
FROM PLAYS PLY1,PLAYS PLY2, PLAYER PLR1, PLAYER PLR2
WHERE PLR1.PID < PLR2.PID AND PLR1.PID = PLY1.PID(+) AND PLR2.PID = PLY2.PID(+)
AND NOT EXISTS(( SELECT PLY3.TEAMID FROM PLAYS PLY3 WHERE PLY3.PID = PLR1.PID)
MINUS
( SELECT PLY4.TEAMID FROM PLAYS PLY4 WHERE PLY4.PID = PLR2.PID));
答案 10 :(得分:0)
select p1.playerId, p2.playerId, count(p1.playerId)
from plays p1, plays p2
WHERE p1.playerId<p2.playerId
and p1.teamId = p2.teamId
GROUP BY p1.playerId, p2.playerId
having count(*) = (select count(*) from plays where playerid = p1.playerid)
答案 11 :(得分:0)
WITH temp AS (
SELECT p.playerid, p.playername, listagg(t.teamname,',') WITHIN GROUP (ORDER BY t.teamname) AS teams
FROM player p full OUTER JOIN plays p1 ON p.playerid = p1.playerid
LEFT JOIN team t ON p1.teamid = t.teamid GROUP BY (p.playerid , p.playername))
SELECT concat(concat(t1.playerid,','), t1.playername), t1.teams
FROM temp t1 WHERE nvl(t1.teams,' ') IN (
SELECT nvl(t2.teams,' ') FROM temp t2
WHERE t1.playerid <> t2.playerid)
ORDER BY t1.playerid
答案 12 :(得分:0)
这是ANSI SQL,不使用任何特殊功能。
SELECT TAB1.T1_playerID AS playerID1 , TAB1.playerName1 ,
TAB1.T2_playerID AS playerID2, TAB1. playerName2
FROM
(select T1.playerID AS T1_playerID , T3. playerName AS playerName1 ,
T2.playerID AS T2_playerID , T4. playerName AS playerName2 ,COUNT (T1.TeamID) AS MATCHING_TEAM_ID_CNT
FROM PLAYS T1
INNER JOIN PLAYS T2 ON( T1.TeamID = T2.TeamID AND T1.playerID <> T2.playerID )
INNER JOIN player T3 ON ( T1.playerID=T3.playerID)
INNER JOIN player T4 ON ( T2.playerID=T4.playerID)
GROUP BY 1,2,3,4
) TAB1
INNER JOIN
( SELECT T1.playerID AS playerID, COUNT(T1.TeamID) AS TOTAL_TEAM_CNT
FROM PLAYS T1
GROUP BY T1.playerID) TAB2
ON(TAB1.T2_playerID=TAB2.playerID AND
TAB1.MATCHING_TEAM_ID_CNT =TAB2.TOTAL_TEAM_CNT)
INNER JOIN
( SELECT T1.playerID AS playerID, COUNT(T1.TeamID) AS TOTAL_TEAM_CNT
FROM PLAYS T1
GROUP BY T1.playerID
) TAB3
ON( TAB1. T1_playerID = TAB3.playerID AND
TAB1.MATCHING_TEAM_ID_CNT=TAB3.TOTAL_TEAM_CNT)
WHERE playerID1 < playerID2
UNION ALL (
SELECT T1.playerID, T1.playerName ,T2.playerID,T2.playerName
FROM
PLAYER T1 INNER JOIN PLAYER T2
ON (T1.playerID<T2.playerID)
WHERE T1.playerID NOT IN ( SELECT playerID FROM PLAYS))
答案 13 :(得分:0)
假设您的teamId是唯一的,则此查询将起作用。它通过对teamid进行求和来简单地识别具有完全相同的团队的所有玩家,或者如果玩家没有id,则它将为null。然后计算团队比赛的比赛次数。我在postgre 9.3中使用SQL小提琴测试。
SELECT
b.playerID
,b.playerName
FROM (
--Join the totals of teams to your player information and then count over the team matches.
SELECT
p.playerID
,p.playerName
,m.TeamMatches
,COUNT(*) OVER(PARTITION BY TeamMatches) as Matches
FROM player p
LEFT JOIN (
--Assuming your teamID is unique as it should be. If it is then a sum of the team ids for a player will give you each team they play for.
--If for some reason your team id is not unique then rank the table and join same as below.
SELECT
ps.playerName
,ps.playerID
,SUM(t.teamID) as TeamMatches
FROM plays p
LEFT JOIN team t ON p.teamID = p.teamID
LEFT JOIN player ps ON p.playerID = ps.playerID
GROUP BY
ps.playerName
,ps.playerID
) m ON p.playerID = m.playerID
) b
WHERE
b.Matches <> 1
答案 14 :(得分:-1)
此查询应该解决它。 通过在PLAYS上自我加入。 - 比较玩家ID - 将匹配的行数与每个玩家的总数进行比较。
select p1.playerId, p2.playerId, count(p1.playerId)
from plays p1, plays p2
WHERE p1.playerId<p2.playerId
and p1.teamId = p2.teamId
GROUP BY p1.playerId, p2.playerId
having count(*) = (select count(*) from plays where playerid = p1.playerid)
&#13;
答案 15 :(得分:-2)
在SQl 2008中创建功能
ALTER FUNCTION [dbo].[fngetTeamIDs] ( @PayerID int ) RETURNS varchar(101) AS Begin
declare @str varchar(1000)
SELECT @str= coalesce(@str + ', ', '') + CAST(a.TeamID AS varchar(100)) FROM (SELECT DISTINCT TeamID from Plays where PayerId=@PayerID) a
return @str
END
- 选择dbo.fngetTeamIDs(2)
查询从这里开始
drop table #temp,#A,#B,#C,#D
(select PayerID,count(*) count
into #temp
from Plays
group by PayerID)
select *
into #A
from #temp as T
where T.count in (
select T1.count from #temp as T1
group by T1.count having count(T1.count)>1
)
select A.*,P.TeamID
into #B
from #A A inner join Plays P
on A.PayerID=P.PayerID
order by A.count
select B.PayerId,B.count,
(
select dbo.fngetTeamIDs(B.PayerId)
) as TeamIDs
into #C
from #B B
group by B.PayerId,B.count
select TeamIDs
into #D
from #c as C
group by C.TeamIDs
having count(C.TeamIDs)>1
select C.PayerId,P.PlayerName,D.TeamIDs
from #D D inner join #C C
on D.TeamIDs=C.TeamIDs
inner join Player P
on C.PayerID=P.PlayerID