[cap-talk] How desirable / feasible is a persistent OCAP language?

ihab.awad at gmail.com ihab.awad at gmail.com
Thu Jul 17 17:22:19 CDT 2008


On Thu, Jul 17, 2008 at 2:59 PM, Mike Samuel <mikesamuel at gmail.com> wrote:

> What's wrong with database triggers?
>

They introduce surprising and often subtle changes in the underlying
dataset, but the semantics of your communication with the dataset do not
permit you to be notified of them.

Say I set a trigger that says, every time Mike submits something to SVN,
give him a 5% salary raise. That's well and fine (especially for Mike). But
the poor person who has implemented a salary viewer app has no clean way to
register as a listener on the "salary" field of the information representing
Mike so as to keep their app up to date. Any data caching they have
implemented is now completely broken since they are implicitly relying on
invariants that don't exist.

If your database were programmed in a ${real_language} and you could
communicate with it via a ${real_protocol}, you can build whatever semantics
you want depending on your application. Yes, it would essentially be a big
pile of "triggers" but, with a real programming system at your disposal, you
could build a real distributed system.

Ihab

-- 
Ihab A.B. Awad, Palo Alto, CA
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.eros-os.org/pipermail/cap-talk/attachments/20080717/c3e97463/attachment.html 


More information about the cap-talk mailing list