Re: Outer Joins

Marc,

I did not look at your queries, but outer joins are supported in the latest development version of PostgreSQL, and will be supported in the upcoming 7.1 release of the software - beta due soon.

Regards,
Grant

Marc Rohloff wrote:

> I've been looking at the open-source databases for a project I am working on and while reading about Postgres I saw that they do not support outer joins yet. I was intrigued by their solution of using a union query.
>
> Something Like:
> select a.col1, b.col2 from a,b where a.col1 = b.col2
> union
> select a.col1, NULL from a where a.col1 not in (select b.col2 from b)
>
> But I was wondering if the following would work (it does in some other databases)
>
> select a.col1, b.col2 from a,b
> where a.col1 = b.col2
> or b.col2 is null
>
> or maybe even
>
> select a.col1, b.col2 from a,b
> where a.col1 = b.col2
> or a.col1 not in (select b.col2 from b)
>
> These would seem to be far more efficient than a union query
> (I would try this but I don't have a Unix box at the moment to install PostgreSQL on!)
>
> Marc Rohloff

--
> Poorly planned software requires a genius to write it
> and a hero to use it.

Grant Finnemore BSc(Eng) (mailto:gaf(at)ucs(dot)co(dot)za)
Software Engineer Universal Computer Services
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