Date: Fri, 23 Apr 93 04:17:27 -0700
From: fernando@afrodita.etsimo.uniovi.es (Fernando Ariznavarreta)
Subject: Changing a tuple creation time.
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	Hello, postgres gurus:
	We are developing an application that needs keep trace of historical
data, so postgres seems to be ideal due to its nice features on archiving and
retriving historical data (data already deleted).

	We would like to use the tools it provides to manage to manage this
(vacuum, purge after some time from deletion, ...)

	Our application models a real life events, and receives the data from 
authomatic sensors in some machines, when a new event happens that replaces 
current one, we want to replace it but archiving old one (to do this we use 
archiving capabilities of postgres).

	The problem is that we don't have access to events exactly as they
happen, there is some delay between the time at wich it happens and the
time we receive it (possibly hours or a day). So when we insert data in
database is some time later the event happened. The sensor system tells us
the time at which it happened.
	We tried to modify 'tmin' attribute to reflect time received from
sensing instruments, 

	append crane( tmin= " DATE HERE"::abstime, ident= "1.2",...)\g

but when we make a retrieve (crane.all,crane.tmin), tmin was reset to
the system creation time.

	Any idea about how to modify tmin by hand ??

	Thanks in advance.
		Fernando,


-- 
Fernando Ariznavarreta Fernandez       E-Mail:fernando@etsimo.uniovi.es
Dpto. Explotacion y Prospeccion de Minas     Phone: +34 8 510 4267
School of Mines. University of Oviedo               +34 8 510 4336
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