Re: Joining three data sources.

On Wed, 19 Jun 2002 12:33:47 +0200
Janning Vygen <vygen@gmx.de> wrote:

> ---------------------
> Result Inter Mailand vs. AC ROM 2:1
> 
> How can i select all games with their results in a tabel like this:
> (i dont care about the team names. this is easy to achieve of course, 
> my question is just about the goals)
> 
> team1_id|team2_id|goals1|goals2
>   1         2       2      1

How about something like this:

SELECT go1.game_id, go1.team1_id, go1.team2_id,         SUM(CASE WHEN go2.team_id = go1.team1_id
THENgo2.n ELSE 0 END) AS goals1,         SUM(CASE WHEN go2.team_id = go1.team2_id                    THEN go2.n ELSE 0
END)AS goals2
 
FROM  (SELECT game_id,                   min(team_id) AS team1_id,                   max(team_id) AS team2_id
 FROM goal            GROUP BY 1) AS go1,         (SELECT game_id, team_id, count(*) AS n              FROM goal
  GROUP BY 1, 2) AS go2
 
WHERE go1.game_id = go2.game_id
GROUP BY 1, 2, 3;



P.S.

As for Goal table, if it has a large number of the rows, you maybe
need to create a unique index on it.

CREATE UNIQUE INDEX idx_goal ON goal(game_id, team_id, minute);



Regards,
Masaru Sugawara