How to get the used time when operate a select query?

Started by Huang@tanpopo-tane.comalmost 24 years ago4 messagesgeneral
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#1Huang@tanpopo-tane.com
huang@tanpopo-tane.com

How can I get the time which a select query use?
thank you!

#2Oskar Berggren
beo@sgs.o.se
In reply to: Huang@tanpopo-tane.com (#1)
Re: How to get the used time when operate a select query?

$B2+=ULP wrote:

How can I get the time which a select query use?
thank you!

If you are using version 7.2 or later, try the command

EXPLAIN ANALYZE <any query>

This will perform the query (even if it is a DELETE FROM <table>!)
and show the actual time.

/Oskar

Ps. You should check what your mail client puts in the from field
of you mail. It is quite unreadable...

--
/----------------------------------------------------------------------\
| Oskar Berggren beo@sgs.o.se |
| Network and Software Engineer SGS Datan�tgrupp |
| Gothenburg, Sweden |
\----------------------------------------------------------------------/

#3Neil Conway
neilc@samurai.com
In reply to: Oskar Berggren (#2)
Re: How to get the used time when operate a select query?

On Thu, Jun 27, 2002 at 12:01:09PM +0200, Oskar Berggren wrote:

$B2+=ULP wrote:

How can I get the time which a select query use?
thank you!

If you are using version 7.2 or later, try the command

EXPLAIN ANALYZE <any query>

This will perform the query (even if it is a DELETE FROM <table>!)
and show the actual time.

BTW in 7.3, you'll be able to do "\timing" inside psql to enable
client-side timing. i.e.

nconway=# \timing
Timing is on.
nconway=# select 1;
?column?
----------
1
(1 row)

Total time: 0.001s
nconway=#

Cheers,

Neil

--
Neil Conway <neilconway@rogers.com>
PGP Key ID: DB3C29FC

#4Tom Lane
tgl@sss.pgh.pa.us
In reply to: Neil Conway (#3)
Re: How to get the used time when operate a select query?

nconway@klamath.dyndns.org (Neil Conway) writes:

BTW in 7.3, you'll be able to do "\timing" inside psql to enable
client-side timing. i.e.

nconway=# select 1;
?column?
----------
1
(1 row)

Total time: 0.001s

Why is the precision of the display restricted to milliseconds?
Clock readings are usually good to a few microseconds on modern
machines.

I'd suggest showing the result in the same format used by EXPLAIN
ANALYZE, which is milliseconds with a fractional part.

regards, tom lane