| From: | Samuel Gendler <sgendler(at)ideasculptor(dot)com> |
|---|---|
| To: | Aaron Burnett <aburnett(at)bzzagent(dot)com> |
| Cc: | "pgsql-sql(at)postgresql(dot)org" <pgsql-sql(at)postgresql(dot)org> |
| Subject: | Re: Drawing a blank on some SQL |
| Date: | 2011-02-12 00:55:10 |
| Message-ID: | AANLkTikLJ6bqjasftLOPx0LV4mfw-ngBoPLw_FdDm9Lh@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-sql |
On Fri, Feb 11, 2011 at 12:47 PM, Aaron Burnett <aburnett(at)bzzagent(dot)com>wrote:
>
>
> Thank you all very much for your help.
>
> The suggestion from Osvaldo below was the best for my situation (not having
> any soret of xref table to join)...
>
>
It may work well for now, but if that foo_activity table has the potential
to get large with only a relatively small percentage of rows fitting in the
date range, it will get very slow compared to the left join, as it requires
loading every row in the table, instead of being able to use an index to
pull just the rows from the date range and then join to the list of valid
activities.
--sam
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Jasen Betts | 2011-02-12 08:09:21 | Re: DELETE FROM takes forever |
| Previous Message | Aaron Burnett | 2011-02-11 20:47:45 | Re: Drawing a blank on some SQL |