Re: Performance on inserts

Alfred Perlstein <bright@wintelcom.net>

From: Alfred Perlstein <bright@wintelcom.net>
To: Matthew Kirkwood <matthew@hairy.beasts.org>
Cc: Jules Bean <jules@jellybean.co.uk>, pgsql-hackers@postgresql.org
Date: 2000-08-26T11:32:51Z
Lists: pgsql-hackers
* Matthew Kirkwood <matthew@hairy.beasts.org> [000826 04:22] wrote:
> On Sat, 26 Aug 2000, Jules Bean wrote:
> 
> > Is there any simple way for Pg to combine inserts into one bulk?
> > Specifically, their effect on the index files.  It has always seemed
> > to me to be one of the (many) glaring flaws in SQL that the INSERT
> > statement only takes one row at a time.
> 
> One of MySQL's little syntax abuses allows:
> 
> INSERT INTO tab (col1, ..) VALUES (val1, ..), (val2, ..);
> 
> which is nice for avoiding database round trips.  It's one
> of the reasons that mysql can do a bulk import so quickly.

That would be an _extremely_ useful feature if it made a difference
in postgresql's insert speed.

> 
> > But, using INSERT ... SELECT, I can imagine that it might be possible
> > to do 'bulk' index updating. so that scanning process is done once per
> > 'batch'.
> 
> Logic for these two cases would be excellent.

We do this sometimes, works pretty nicely.

-- 
-Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org]
"I have the heart of a child; I keep it in a jar on my desk."