Re: Indexes not used in DELETE

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Tom,

I should have looked at the analyzed plan first. The culprit for the slow query were trigger function calls on foreign keys.

Ciao,
Viktor

Am 08.05.2009 um 01:06 schrieb Tom Lane:

Viktor Rosenfeld <rosenfel@xxxxxxxxxxxxxxxxxxxxxxx> writes:
-> Seq Scan on corpus toplevel (cost=0.00..1.39 rows=1 width=54) Filter: (top_level AND (id = 25::numeric))

Specifically, I'm wondering why the innermost scan on corpus
(toplevel) does not use the index idx_corpus__toplevel

The cost estimate indicates that there are so few rows in corpus
that an indexscan would be a waste of time.

and why the
join between corpus (toplevel) and corpus (child) is not a merge join
using the index corpus_pre_key to access the child table.

Same answer.  Populate the table and the plan will change.

			regards, tom lane

--
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx )
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance


--
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance

[Postgresql General]     [Postgresql PHP]     [PHP Users]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Yosemite]

  Powered by Linux