Re: Howto prevent write based on date

[Franco Bruno Borghesi <fborghesi@xxxxxxxxx>]

You could write a trigger like this:


CREATE OR REPLACE FUNCTION checkDate() RETURNS TRIGGER LANGUAGE 'plpgsql' AS '
DECLARE
	limitDate DATE DEFAULT current_date-''1 year''::INTERVAL;
BEGIN
	IF (OLD.date<=limitDate) THEN
		RAISE EXCEPTION ''Cannot change record.'';
	END IF;

	RETURN NEW;
END;
';

CREATE TRIGGER xxxx_tg1 BEFORE UPDATE OR DELETE ON xxxx FOR EACH ROW EXECUTE PROCEDURE checkDate();

This should do the job :)

2005/5/4, Fmiser <fmiser@xxxxxxxxx>:

I'm a newbie to database admin, but I'm not afraid to try - but this one
has me stumped.

I'm using SQL-Ledger as a front end to postgresql 7.4.2. on (mostly)
Debian Testing, i386.

My fiscal year is over and I would _like_ to prevent any changes to the
data from last year.

I looked/searched in the manual, but I don't even know what to call what
it is that I'm trying to do!

"lock" has another meaning for databases. :)

"Write" seems to bring up lots of user-related stuff.

So, I'm hoping one of you geniuses can tell me where to look, what to
look for, or how to do it. *smile*

Thanks!

               Philip, wanabe-admin

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