Re: join queries

"David M. Kaplan" wrote:
>Hi,
>
>I have a query which seems like it should easy, but isnt. I have two
>tables, a and b that look like this:
>
>a)
>
> id | c1
>--+--
> 1 | a
> 2 | b
> 3 | c
>
>b)
>
> id | c2
>--+--
> 2 | b
>
>and I would like to do a query which returns
>
> id | c1 | c2
>--+--+--
> 1 | a |
> 2 | b | b
> 3 | c |
>
>The simplest thing I could find was
>
>SELECT a.*, (SELECT b.c2 WHERE a.id=b.id) AS c2;
>
>This works, but is extremely slow for more complex examples. Is there a
>better way to do this in postgresql?? I think MS Access has inner and
>outer joins to solve this problem. Is there a postgresql equivalent?

SELECT a.id, c1, c2 FROM a LEFT OUTER JOIN b ON a.id = b.id

This requires PostgreSQL 7.1

--
Oliver Elphick Oliver(dot)Elphick(at)lfix(dot)co(dot)uk
Isle of Wight http://www.lfix.co.uk/oliver
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