From: | Gregory Wood <gwood(at)ewebengine(dot)com> |
---|---|
To: | Anony Mous <a(dot)mous(at)shaw(dot)ca> |
Cc: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: Two joins on same foreign key |
Date: | 2004-01-30 22:43:09 |
Message-ID: | 401ADDFD.7000201@ewebengine.com |
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Thread: | |
Lists: | pgsql-general |
> I’m fairly new to this database, and have read much discussion on
> sub-queries. I’ve seen that they can be great for some queries, and
> downright slow for others. I have a table with two foreign keys
> referencing another table, like:
>
> Table #1
>
> employee_id (pk)
>
> employee_name
>
> Table #2
>
> teamleader_employee_id
>
> backup_employee_id
>
> both fields in table 2 need to do a lookup in table 1 to get the name of
> the actual employee. Do I need to use nested queries to accomplish
> this? Any help is greatly appreciated!
Just do two joins against the first table:
SELECT *
FROM table2
JOIN table1 tl ON (teamleader_employee_id=tl.employee_id)
JOIN table1 b ON (backup_employee_id=b.employee_id);
Greg
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