Hi,
On 02/15/2013 10:46 PM, Cédric Villemain wrote:
Hello,
I'm also interested in this topic.
> > I'm also interested in this topic and work on system-time temporal
> > extension. Here I wrote down design of my solution few months ago
> > https://wiki.postgresql.org/wiki/SQL2011Temporal. The idea is
> > basically the same as in your solution with some minor differences.
I've added a requirement in the system here: the table to be versioned
must have a PK (I dislike _entry_id usage but this sounds good othwise).
I then define a "EXCLUDE WITH GIST (pk with =, sys_period with &&)", thus
getting expected UNIQUEness also in the history.
I use similar constraints for application-time period tables but not for
system versioned. Because they are automatically controlled by a
trigger, there should be no need for additional integrity checks. If you
want to speed up queries against historical data, you can create GIST
index or an exclusion constraint.
Vlad, is your source code in a public versionning system (github,
bucket, etc) ?
It will ease the process to participate to your extension...
Yes, I uploaded it on github
https://github.com/arkhipov/temporal_tables/
The extension is also available on PGXN
http://pgxn.org/dist/temporal_tables/1.0.0/
--
Cédric Villemain +33 (0)6 20 30 22 52
http://2ndQuadrant.fr/
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