Re: running maintenance tasks on DB

On Sat, Sep 23, 2000 at 05:26:47PM +0200, Louis-David Mitterrand wrote:
> Approaching completion of an online auction system based on Postgres and
> mod_perl/Apache I yet have to devise a good way of running certain
> maintenance tasks on the DB like closing auctions, notifying winners,
> transferring old records to archive tables, etc.
>
> What is the usual way of programming such tasks? Write a backend
> function (in pl/sql or C) and call it from a cron job? From a mod_perl
> handler?

I don't know if this is the best way, but I usually just write a Perl
script and run it through cron. You just have to make sure that you
maintain data integrity while doing maintainence - i.e. there is no
point where the data is invalid. This usually means putting stuff
into transactions, but that's no big deal.

I don't believe you can get backend functions to run at certain
times, without using a mechanism like cron to connect to the DB and
run them.

A mod_perl handler is a totally different matter. That's for doing
stuff with HTTP requests - isn't this unrelated? I would think that
you'd have mod_perl handlers displaying your content and manipulating
the DB, and have some scripts set to run every X minutes/hours which
do maintainence.

I use Perl, but you can obviously use any language you like, provided
it has a Postgres interface.

HTH,

Neil

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