Re: Postgres code for a query intermediate dataset - Mailing list pgsql-hackers

On Sat, Sep 13, 2014 at 11:52 PM, David G Johnston <david.g.johnston@gmail.com> wrote:

Atri Sharma wrote
> On Sat, Sep 13, 2014 at 11:06 PM, Rohit Goyal &lt;



Or rather even if you want to be able to reference the older versions of
that record there is nothing in PostgreSQL to facilitate that. You have to
manually create and manage the data so that you know during what time period
a given record is valid.

David J.

Sometimes I do miss 'time travel' we used to have :)

Regards,

Atri

--

Regards,

 

Atri

l'apprenant

That is only because the Guild of Time Travellers was formed, and we are very selective in whom we allow to join.  It was a massive undertaking to purge the knowledge of effective time travel from the general populace (H. G. Wells had to be expelled with a partial brain wipe)!   :-)

On a more serious note:
I did design and implement a system to allow what the original poster was after, it involved 2 tables for each logical table, and used both an EFFECTIVE_DATE & an AS_AT_DATE.  This allowed insurance quotes to be valid for a given of time, even if the insurance rates were set change after the quote was given (but before the quote expired).  This was about 15 years ago. It was amusing that my wife joined that team 10 years after I left, and found 2 of my original colleagues still there!


Cheers,
Gavin