Re: (long) What's the problem? - Mailing list pgsql-sql

From Jan Wieck
Subject Re: (long) What's the problem?
Date
Msg-id 3EE35169.8000706@Yahoo.com
Whole thread Raw
In response to (long) What's the problem?  ("David Olbersen" <DOlbersen@stbernard.com>)
List pgsql-sql
David Olbersen wrote:
> Anybody have any ideas about a problem with this query?
> 
> urldb2=> EXPLAIN
> urldb2-> SELECT
> urldb2->   id,
> urldb2->   source,
> urldb2->   insertedby,
> urldb2->   insertedon,
> urldb2->   priority
> urldb2-> FROM
> urldb2->   indexscan
> urldb2-> WHERE
> urldb2->   lower(
> urldb2->     substring(
> urldb2->       urlhost( source ), rposition( 'www.', urlhost( source ) ) + 2
> urldb2->     )
> urldb2->   ) ~ '^q.*'
> urldb2-> ORDER BY source;                                                                
> 
> QUERY PLAN                                     
>
-------------------------------------------------------------------------------------------------------------------------------------------
>  Sort  (cost=23.50..23.50 rows=3 width=48)
>    Sort Key: source
>    ->  Seq Scan on indexscan  (cost=0.00..23.47 rows=3 width=48)
>          Filter: (lower("substring"(urlhost(source), (rposition('www.'::text, (urlhost(source))::character varying) +
2)))~ '^q.*'::text)
 
> (4 rows)
> 
> OK, cost=23.50..23.50, should be a quickie. I'll EXPLAIN ANALYZE just to be safe:
> 
> urldb2=> EXPLAIN ANALYZE
> urldb2-> SELECT
> urldb2->   id,
> urldb2->   source,
> urldb2->   insertedby,
> urldb2->   insertedon,
> urldb2->   priority
> urldb2-> FROM
> urldb2->   indexscan
> urldb2-> WHERE
> urldb2->   lower(
> urldb2->     substring(
> urldb2->       urlhost( source ), rposition( 'www.', urlhost( source ) ) + 2
> urldb2->     )
> urldb2->   ) ~ '^q.*'
> urldb2-> ORDER BY source;
> 
> server closed the connection unexpectedly
>         This probably means the server terminated abnormally
>         before or while processing the request.
> The connection to the server was lost. Attempting reset: Failed.

If I would be you I would unlimit the coresize in the environment the 
postmaster is running, eventually recompile with debug symbols enabled 
and look at the stack backtrace of the coredump created when then 
backend crashes.


Jan

-- 
#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#================================================== JanWieck@Yahoo.com #



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