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help / color / mirror / Atom feedRe: *** PROBABLY SPAM *** Does the psql executable support a "fetch many" approach when dumping large queries to stdout?
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* Re: *** PROBABLY SPAM *** Does the psql executable support a "fetch many" approach when dumping large queries to stdout?
@ 2010-04-02 20:43 Pierre C <lists@peufeu.com>
0 siblings, 2 replies; 3+ messages in thread
From: Pierre C @ 2010-04-02 20:43 UTC (permalink / raw)
To: Beaver, John E <John_Beaver@hms.harvard.edu>; pgsql-performance
> Does the psql executable have any ability to do a "fetch many", using a
> server-side named cursor, when returning results? It seems like it tries
> to retrieve the query entirely to local memory before printing to
> standard out.
I think it grabs the whole result set to calculate the display column
widths. I think there is an option to tweak this but don't remember which,
have a look at the psql commands (\?), formatting section.
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: *** PROBABLY SPAM *** Does the psql executable support a "fetch many" approach when dumping large queries to stdout?
@ 2010-04-02 22:19 John Beaver <john_beaver@hms.harvard.edu>
parent: Pierre C <lists@peufeu.com>
1 sibling, 0 replies; 3+ messages in thread
From: John Beaver @ 2010-04-02 22:19 UTC (permalink / raw)
To: Pierre C <lists@peufeu.com>; +Cc: pgsql-performance
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=UTF-8" http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
That makes sense. I'll just use a COPY statement instead like Hannu
suggests.<br>
<br>
Pierre C wrote:
<blockquote cite="mid:op.vajyiejneorkce@immo.peufeu.com" type="cite">
<blockquote type="cite">
<pre wrap="">Does the psql executable have any ability to do a "fetch many", using a
server-side named cursor, when returning results? It seems like it tries
to retrieve the query entirely to local memory before printing to
standard out.
</pre>
</blockquote>
<pre wrap=""><!---->
I think it grabs the whole result set to calculate the display column
widths. I think there is an option to tweak this but don't remember which,
have a look at the psql commands (\?), formatting section.
</pre>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
John E. Beaver
Bioinformatics Developer
Harvard Medical School</pre>
</body>
</html>
^ permalink raw reply [nested|flat] 3+ messages in thread
* Re: *** PROBABLY SPAM *** Does the psql executable support a "fetch many" approach when dumping large queries to stdout?
@ 2010-04-13 02:49 Bruce Momjian <bruce@momjian.us>
parent: Pierre C <lists@peufeu.com>
1 sibling, 0 replies; 3+ messages in thread
From: Bruce Momjian @ 2010-04-13 02:49 UTC (permalink / raw)
To: Pierre C <lists@peufeu.com>; +Cc: Beaver, John E <John_Beaver@hms.harvard.edu>; pgsql-performance
Pierre C wrote:
> > Does the psql executable have any ability to do a "fetch many", using a
> > server-side named cursor, when returning results? It seems like it tries
> > to retrieve the query entirely to local memory before printing to
> > standard out.
>
> I think it grabs the whole result set to calculate the display column
> widths. I think there is an option to tweak this but don't remember which,
> have a look at the psql commands (\?), formatting section.
See the FETCH_COUNT variable mentioned in the psql manual page.
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
^ permalink raw reply [nested|flat] 3+ messages in thread
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2010-04-02 20:43 Re: *** PROBABLY SPAM *** Does the psql executable support a "fetch many" approach when dumping large queries to stdout? Pierre C <lists@peufeu.com>
2010-04-02 22:19 ` John Beaver <john_beaver@hms.harvard.edu>
2010-04-13 02:49 ` Bruce Momjian <bruce@momjian.us>
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