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* query for records based on date
@ 2005-02-21 20:00 Brandon Metcalf <bmetcalf@nortel.com>
2005-02-21 20:42 ` Re: query for records based on date Martín Marqués <martin@bugs.unl.edu.ar>
2005-02-21 20:53 ` Re: query for records based on date Richard Huxton <dev@archonet.com>
0 siblings, 2 replies; 4+ messages in thread
From: Brandon Metcalf @ 2005-02-21 20:00 UTC (permalink / raw)
To: pgsql-sql
If I have a table with an attribute of type "timestamp without time
zone", what is the best way to query that table for records that are
older than, say, one week.
I suppose I could get the current time in epoch seconds and the time of
the attribute in the same, and select those records where the difference
is greater than the number of seconds in a week. Is there something
easier like
SELECT * FROM table WHERE attribute IS OLDER THAN one week;
Thanks.
--
Brandon
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: query for records based on date
2005-02-21 20:00 query for records based on date Brandon Metcalf <bmetcalf@nortel.com>
@ 2005-02-21 20:42 ` Martín Marqués <martin@bugs.unl.edu.ar>
2005-02-21 20:48 ` Re: query for records based on date Brandon Metcalf <bmetcalf@nortel.com>
1 sibling, 1 reply; 4+ messages in thread
From: Martín Marqués @ 2005-02-21 20:42 UTC (permalink / raw)
To: Brandon Metcalf <bmetcalf@nortel.com>; +Cc: pgsql-sql
El Lun 21 Feb 2005 17:00, Brandon Metcalf escribió:
> If I have a table with an attribute of type "timestamp without time
> zone", what is the best way to query that table for records that are
> older than, say, one week.
>
> I suppose I could get the current time in epoch seconds and the time of
> the attribute in the same, and select those records where the difference
> is greater than the number of seconds in a week. Is there something
> easier like
>
> SELECT * FROM table WHERE attribute IS OLDER THAN one week;
SELECT * FROM table WHERE attribute < (now()::DATE - 7)::TIMESTAMP;
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Martín Marqués | select 'mmarques' || '@' || 'unl.edu.ar'
Centro de Telematica | DBA, Programador, Administrador
Universidad Nacional
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^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: query for records based on date
2005-02-21 20:00 query for records based on date Brandon Metcalf <bmetcalf@nortel.com>
2005-02-21 20:42 ` Re: query for records based on date Martín Marqués <martin@bugs.unl.edu.ar>
@ 2005-02-21 20:48 ` Brandon Metcalf <bmetcalf@nortel.com>
0 siblings, 0 replies; 4+ messages in thread
From: Brandon Metcalf @ 2005-02-21 20:48 UTC (permalink / raw)
To: Martín Marqués <martin@bugs.unl.edu.ar>; +Cc: pgsql-sql
m == martin@bugs.unl.edu.ar writes:
m> El Lun 21 Feb 2005 17:00, Brandon Metcalf escribió:
m> > If I have a table with an attribute of type "timestamp without time
m> > zone", what is the best way to query that table for records that are
m> > older than, say, one week.
m> >
m> > I suppose I could get the current time in epoch seconds and the time of
m> > the attribute in the same, and select those records where the difference
m> > is greater than the number of seconds in a week. Is there something
m> > easier like
m> >
m> > SELECT * FROM table WHERE attribute IS OLDER THAN one week;
m> SELECT * FROM table WHERE attribute < (now()::DATE - 7)::TIMESTAMP;
Thanks.
--
Brandon
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: query for records based on date
2005-02-21 20:00 query for records based on date Brandon Metcalf <bmetcalf@nortel.com>
@ 2005-02-21 20:53 ` Richard Huxton <dev@archonet.com>
1 sibling, 0 replies; 4+ messages in thread
From: Richard Huxton @ 2005-02-21 20:53 UTC (permalink / raw)
To: Brandon Metcalf <bmetcalf@nortel.com>; +Cc: pgsql-sql
Brandon Metcalf wrote:
> If I have a table with an attribute of type "timestamp without time
> zone", what is the best way to query that table for records that are
> older than, say, one week.
>
> I suppose I could get the current time in epoch seconds and the time of
> the attribute in the same, and select those records where the difference
> is greater than the number of seconds in a week. Is there something
> easier like
>
> SELECT * FROM table WHERE attribute IS OLDER THAN one week;
Look up "intervals" in the manuals - you can just subtract timestamps/dates.
Probably also worth searching the mailing lists for "ago()" and
"volatile" to learn about the issues with indexing.
--
Richard Huxton
Archonet Ltd
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2005-02-21 20:00 query for records based on date Brandon Metcalf <bmetcalf@nortel.com>
2005-02-21 20:42 ` Martín Marqués <martin@bugs.unl.edu.ar>
2005-02-21 20:48 ` Brandon Metcalf <bmetcalf@nortel.com>
2005-02-21 20:53 ` Richard Huxton <dev@archonet.com>
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