Thanks for all people. And Michael, I think your researches are very close
to my researches. I'm looking for partnership (I hope this is the correct
word).
Although, this area is very old (about 20 years), there is not much
implementation. I saw the architecture of BTPGSQL, and is a usual
implementation where it was developed a API to do the interface between the
aplication and the data. It's a good solution, but not what I'm looking for.
I'm looking for something implemented inside the database, like the
flashback functionality of oracle 10g.
And thanks Michael, I will have a look on the Date's article.
----- Original Message -----
From: "Michael Glaesemann" <grzm@xxxxxxxxxxxxx>
To: "Rodrigo Sakai" <rodrigo.sakai@xxxxxxxxxxx>
Cc: <pgsql-general@xxxxxxxxxxxxxx>
Sent: Thursday, February 23, 2006 10:43 PM
Subject: Re: [GENERAL] Temporal Databases
On Feb 24, 2006, at 3:34 , Rodrigo Sakai wrote:
I'm focus on temporal databases (not temporary), and I want to know if
anyone here is studying this tecnologies too. So, we can exchange
knowlegment. Specifically, anyone who is trying to implement on
postgresql the aspect of time (temporal).
These researches are lead by Richard Snodgrass. So, anyone who have
something to share, please contact me!
Nice to meet you, Rodrigo. This is an area that I hope to do some work on
as well.
Another resource that you may find useful is Date, Darwen, and Lorentzos'
"Temporal Data and the Relational Model" which starts from temporal data
in particular and proposes a more generalized "interval" data type
constructor. Lorentzos has also published some articles on IXSQL[2] which
you may find interesting in its extensions to SQL in particular, rather
than the relational model.
You may also be interested to know there is an no-longer documented
tinterval type in Postgres. I don't believe it's even been tested in
recent years, but you may want to look at its implementation.
Michael Glaesemann
grzm myrealbox com
[1](http://www.amazon.com/gp/product/1558608559/)
[2] Nikos A. Lorentzos and Yannis G. Mitsopoulos, "SQL Extension for
Interval Data", IEEE Transactions On Knowledge And Data Engineering,
Vol. 9, No. 3, May/June 1997
