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Re: How to fetch values at regular hours?

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Goran Hasse wrote:
Hello all!

I am logging my electricity meeter every five minute!

But the problem is that I would like to get values *just before* every hour - like

select * from counter_log_view where name='CNT-3' and timestamp < '2010-05-23 22:00:00' order by timestamp desc limit 1;
 name  |         timestamp          | count
-------+----------------------------+-------
 CNT-3 | 2010-05-23 21:53:20.844422 |    69
(1 rad)

But I don't want to do a lot of selections and gather all the data in a file. Is there any better way to create the query so that I get the values just before
every hour?

wild guess, untested..  something like...

select * from counter_log_view where name = 'CNT-3' and extract(minute from timestamp) >= 55 order by timestamp;



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