Re: Representation for Deleted Entities: difficult question

From: Leandro Guimarães Faria Corsetti Dutra <leandro_at_dutra.fastmail.fm>
Date: Thu, 13 May 2004 16:40:55 -0300
Message-ID: <pan.2004.05.13.19.40.52.493293@dutra.fastmail.fm>

Em Thu, 13 May 2004 11:32:21 -0700, Robert Brown escreveu:

> I pointed out that it is not as simple as that because the user
> entity is related to many, many others so we would have to add this
> "deleted" flag to every relationship and every other entity and thus
> have "deleted" past purchases, "deleted" affiliations - a whole
> shadow schema full of such ghost entities.

I really see no problem. It is just a few entities that are, not quite deleted but actually 'deactivated'. All the others exist in relation to these, thus a simple join with a selection clause will do.

There is a performance hit, but this is the price of doing business...

The alternative would be to have a real shadow database or schema where data would be moved when deleted from the main one, but I guess the performance hit would be worse, besides all the application changes and added maintainance.

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Received on Thu May 13 2004 - 14:40:55 CDT