SPAM!!!: SPAM!!!: Re: SPAM!!!: Re: [UMN_MAPSERVER-USERS] JOIN / ODBC

[Frank Warmerdam]

On 11/24/05, Sylvain Beorchia <sbeorchia at gi-lemans.com> wrote:
> Hi,
>
> This works. I've tried it yesterday...that's really cool, i was looking for
> that functionnality for a long time...
> But it's very slow, very very slow.. or maybe i don't use it like i should
> do ?
> The only way i found to get it faster is to have a small shapfile, and a
> small database....
>
> If someone tried this method, and can give me any advices.

Sylvain,

I think the best way to make it fast is to put everything
within one real RDBMS.  Then the join can be done
in the database.  My approach of having to issue a
separate SELECT for record needed from the joined
database is inevitably high overhead.

Of course, it is also critical to have the joined database
indexed on the id used in the join.

Best regards,
--
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