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

2008-03-06 Thread Joris Dobbelsteen
>-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 co

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

2008-03-04 Thread Tom Lane
"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. >

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

2008-03-04 Thread Joris Dobbelsteen
ter "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 >>

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

2008-02-25 Thread Joris Dobbelsteen
@postgresql.org >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=

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

2008-02-25 Thread Joris Dobbelsteen
>-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 co

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

2008-02-25 Thread Tom Lane
"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.

2008-02-25 Thread Joris Dobbelsteen
>-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]> writ

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

2008-02-25 Thread Gregory Stark
"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)

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

2008-02-25 Thread Joris Dobbelsteen
>-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. > >O

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

2008-02-24 Thread Scott Marlowe
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" a

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

2008-02-24 Thread Joris Dobbelsteen
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,