Re: PostgreSQL performance in simple queries

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Joseph Shraibman <jks(at)selectacast(dot)net>
Cc: pgsql-performance(at)postgresql(dot)org, Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
Subject: Re: PostgreSQL performance in simple queries
Date: 2004-05-20 15:33:59
Message-ID: 1454.1085067239@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-performance

Joseph Shraibman <jks(at)selectacast(dot)net> writes:
> Neil Conway wrote:
>> PostgreSQL (< 7.5) won't consider using an indexscan when the predicate
>> involves an integer literal and the column datatype is int2 or int8.

> Is this fixed for 7.5? It isn't checked off on the TODO list at
> http://developer.postgresql.org/todo.php

It is. I don't know why Bruce hasn't checked it off.

Some other stuff that needs work in TODO:

: Bracketed items "[]" have more detailed.

More detailed what? Grammar please.

: * Remove unreferenced table files and temp tables during database vacuum
: or postmaster startup (Bruce)

I'm not sure this is still needed given that we now log file deletion in
WAL.

: * Allow pg_dump to dump sequences using NO_MAXVALUE and NO_MINVALUE

Seems to be done.

: * Prevent whole-row references from leaking memory, e.g. SELECT COUNT(tab.*)

Done.

: * Make LENGTH() of CHAR() not count trailing spaces

Done.

: * Allow SELECT * FROM tab WHERE int2col = 4 to use int2col index, int8,
: float4, numeric/decimal too

Done, per above.

: * Allow more ISOLATION LEVELS to be accepted, but issue a warning for them

Presently we accept all four with no warning ...

: * Add GUC setting to make created tables default to WITHOUT OIDS

Seems to be done, other than the argument about how pg_dump should work.

: * Allow fastpast to pass values in portable format

This was done in 7.4.

: * Move psql backslash database information into the backend, use nmumonic
: commands? [psql]

Spelling problem...

: * JDBC

With JDBC out of the core, I'm not sure why we still have a JDBC section
in the core TODO.

: * Have pg_dump -c clear the database using dependency information

I think this works now. Not really tested, but in principle it should
work.

: * Cache last known per-tuple offsets to speed long tuple access

This sounds exactly like attcacheoff, which has been there since
Berkeley. Either remove this or fix the description to give some
idea what's really meant.

: * Automatically place fixed-width, NOT NULL columns first in a table

This is not ever going to happen, given that we've rejected the idea of
having separate logical and physical column positions.

: * Change representation of whole-tuple parameters to functions

Done. (However, you might want to add something about supporting
composite types as table columns, which isn't done.)

: * Allow the regression tests to start postmaster with -i so the tests
: can be run on systems that don't support unix-domain sockets

Done long ago.

regards, tom lane

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Bruce Momjian 2004-05-20 15:56:55 Re: PostgreSQL performance in simple queries
Previous Message Tom Lane 2004-05-20 14:41:05 Re: add server include files to default installation?

Browse pgsql-performance by date

  From Date Subject
Next Message Bruce Momjian 2004-05-20 15:56:55 Re: PostgreSQL performance in simple queries
Previous Message Marty Scholes 2004-05-20 13:46:08 Re: Hardware Platform