Hi ,
I am having some trouble with postgres 8.0 ,
I have a basic query over a few tables
qe_quizzes,insrel,qe_content,posrel,qe_categories
but that query takes about 10 seconds.....
an explain on that query shows that postgress will perform a Seq Scan
on all tables that extend insrel
-> Seq Scan on mm_insrel insrel (cost=0.00..25.79
rows=1279 width=8)
-> Seq Scan on mm_posrel insrel (cost=0.00..75.86
rows=2586 width=8)
-> Seq Scan on mm_qe_resultrel insrel
(cost=0.00..1545.99 rows=79899 width=8)
First of all I don't unserstand why postgress is performing a sequence scan.
but anyway. I turned inheritance off for the relation builders by
using the "ONLY" keyword and this seams to greatly improve
performance. the cost went from 498357 to 33949
see
http://carlit.mine.nu/~keesj/query.stuff.html
Is there any way we can change the generated sql to use the only
keyword when performing queries over insrel?
greetings
_______________________________________________
Developers mailing list
[email protected]
http://lists.mmbase.org/mailman/listinfo/developers
