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* looking to speed up SELECT ... LEFT JOIN query
@ 2002-08-07 05:03 Trey Ackerman <ta145@yahoo.com>
2002-08-08 14:24 ` Re: looking to speed up SELECT ... LEFT JOIN query Richard Huxton <dev@archonet.com>
0 siblings, 1 reply; 2+ messages in thread
From: ta145@yahoo.com @ 2002-08-07 05:03 UTC (permalink / raw)
To: pgsql-general@postgresql.org; pgsql-php@postgresql.org; pgsql-sql
Hi,
I have a working SELECT statement using LEFT JOIN but I'm hoping
someone can suggest something that might be a bit quicker (currently 3
seconds for result).
SELECT * FROM ((table1 LEFT JOIN table2 USING (custno)) AS j1
LEFT JOIN table3 USING (custno)) AS j2
LEFT JOIN table4 USING (custno)
WHERE custno='$custno';
The primary table is table1, the key for all tables is 'custno'. I
need the LEFT JOIN because any one or all of the other tables (table2,
table3, table4) might not have corresponding data.
Regards,
Trey Ackerman
^ permalink raw reply [nested|flat] 2+ messages in thread
* Re: looking to speed up SELECT ... LEFT JOIN query
2002-08-07 05:03 looking to speed up SELECT ... LEFT JOIN query Trey Ackerman <ta145@yahoo.com>
@ 2002-08-08 14:24 ` Richard Huxton <dev@archonet.com>
0 siblings, 0 replies; 2+ messages in thread
From: Richard Huxton @ 2002-08-08 14:24 UTC (permalink / raw)
To: ta145@yahoo.com; pgsql-general@postgresql.org; pgsql-php@postgresql.org; pgsql-sql
On Wednesday 07 Aug 2002 6:03 am, Trey Ackerman wrote:
> Hi,
>
> I have a working SELECT statement using LEFT JOIN but I'm hoping
> someone can suggest something that might be a bit quicker (currently 3
> seconds for result).
>
> SELECT * FROM ((table1 LEFT JOIN table2 USING (custno)) AS j1
> LEFT JOIN table3 USING (custno)) AS j2
> LEFT JOIN table4 USING (custno)
> WHERE custno='$custno';
>
> The primary table is table1, the key for all tables is 'custno'. I
> need the LEFT JOIN because any one or all of the other tables (table2,
> table3, table4) might not have corresponding data.
We'll need to see the output of an EXPLAIN / EXPLAIN ANALYSE - also could you
join the tables in a different order, smallest first?
- Richard Huxton
^ permalink raw reply [nested|flat] 2+ messages in thread
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2002-08-07 05:03 looking to speed up SELECT ... LEFT JOIN query Trey Ackerman <ta145@yahoo.com>
2002-08-08 14:24 ` Richard Huxton <dev@archonet.com>
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