Re: [GENERAL] Planner: rows=1 after similar to where condition.

-Original Message- From: Tom Lane [mailto:[EMAIL PROTECTED] Sent: Wednesday, 5 March 2008 0:29 To: Joris Dobbelsteen Cc: Gregory Stark; Scott Marlowe; pgsql-general@postgresql.org Subject: Re: [GENERAL] Planner: rows=1 after similar to where condition. Joris Dobbelsteen [EMAIL

Re: [GENERAL] Planner: rows=1 after similar to where condition.

-Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Joris Dobbelsteen Sent: Monday, 25 February 2008 17:08 To: Tom Lane Cc: Gregory Stark; Scott Marlowe; pgsql-general@postgresql.org Subject: Re: [GENERAL] Planner: rows=1 after similar to where condition

Re: [GENERAL] Planner: rows=1 after similar to where condition.

Joris Dobbelsteen [EMAIL PROTECTED] writes: From: Tom Lane [mailto:[EMAIL PROTECTED] If you increase the stats target for the column to 100 or more then it will try actually applying the regexp to all the histogram entries. That might or might not give you a better estimate. A new test

Re: [GENERAL] Planner: rows=1 after similar to where condition.

-Original Message- From: Scott Marlowe [mailto:[EMAIL PROTECTED] Sent: Monday, 25 February 2008 7:14 To: Joris Dobbelsteen Cc: pgsql-general@postgresql.org Subject: Re: [GENERAL] Planner: rows=1 after similar to where condition. On Sun, Feb 24, 2008 at 4:35 PM, Joris Dobbelsteen [EMAIL

Re: [GENERAL] Planner: rows=1 after similar to where condition.

Joris Dobbelsteen [EMAIL PROTECTED] writes: Should be: PostGreSQL 8.2.5 on x86_64-pc-linux-gnu (GCC 4.1.2.20061115) (Debian 4.1.1-21). In this case that may matter. One of the changes in the 8.2.6 update was: . Improve planner's handling of LIKE/regex estimation in non-C locales (Tom) I

Re: [GENERAL] Planner: rows=1 after similar to where condition.

-Original Message- From: Gregory Stark [mailto:[EMAIL PROTECTED] Sent: Monday, 25 February 2008 12:31 To: Joris Dobbelsteen Cc: Scott Marlowe; pgsql-general@postgresql.org Subject: Re: Planner: rows=1 after similar to where condition. Joris Dobbelsteen [EMAIL PROTECTED] writes: Should

Re: [GENERAL] Planner: rows=1 after similar to where condition.

Joris Dobbelsteen [EMAIL PROTECTED] writes: Bitmap Heap Scan on log_syslog syslog (cost=11168.32..16988.84 rows=1 width=221) (actual time=11145.729..30067.606 rows=212 loops=1) Recheck Cond: (((program)::text = 'amavis'::text) AND ((facility)::text = 'mail'::text)) Filter:

Re: [GENERAL] Planner: rows=1 after similar to where condition.

Subject: Re: [GENERAL] Planner: rows=1 after similar to where condition. Joris Dobbelsteen [EMAIL PROTECTED] writes: Bitmap Heap Scan on log_syslog syslog (cost=11168.32..16988.84 rows=1 width=221) (actual time=11145.729..30067.606 rows=212 loops=1) Recheck Cond: (((program)::text = 'amavis

Re: [GENERAL] Planner: rows=1 after similar to where condition.

-Original Message- From: Tom Lane [mailto:[EMAIL PROTECTED] Sent: Monday, 25 February 2008 16:34 To: Joris Dobbelsteen Cc: Gregory Stark; Scott Marlowe; pgsql-general@postgresql.org Subject: Re: [GENERAL] Planner: rows=1 after similar to where condition. Joris Dobbelsteen [EMAIL

[GENERAL] Planner: rows=1 after similar to where condition.

I seem to have some planner oddity, where it seems to completely mispredict the output after a regex compare. I've seem it on other occasions, where it completely screws up the join. You can note the rows=1 after the filter. A similar sitution has occurred when doing a regex filter in a subquery,

Re: [GENERAL] Planner: rows=1 after similar to where condition.

On Sun, Feb 24, 2008 at 4:35 PM, Joris Dobbelsteen [EMAIL PROTECTED] wrote: I seem to have some planner oddity, where it seems to completely mispredict the output after a regex compare. I've seem it on other occasions, where it completely screws up the join. You can note the rows=1 after