Re: ON INSERT => execute AWK/SH/EXE?

bima(dot)djaloeis(dot)uni(at)googlemail(dot)com ("Bima Djaloeis") writes:
> Hi there,
> I am new to PostgreSQL, is it possible to create something so that
> 1) If I insert / update / delete an item from my DB...
> 2) ... an awk / shell / external program is executed in my UNIX System?
> If yes, how do I do this and if no, thanks for telling.
> Thanks for reading, any help is appreciated.

I Would Not try to do that directly, as that could lead to arbitrary
numbers of processes getting scheduled, which could cause Plenty O
Heartburn.

I would instead suggest having a trigger in place that would, upon
doing this:

a) Insert an ID, if needed, into a work queue table.
(This may be optional.)

b) Use NOTIFY to tell a process that uses LISTEN to wake up and
do whatever work is necessary, possibly processing *multiple*
items.

The LISTENING process needs to be prepared to process all the
queued-up work; that should lead to *vastly* more efficient processing
than spawning a worker for each item.
--
"cbbrowne","@","acm.org"
http://www3.sympatico.ca/cbbrowne/rdbms.html
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