organizing cron jobs in one function

Hi,

I'm planning to centralize all db maintenance jobs from a single
pl/pgsql function called by cron every 15 minutes (highest frequency
required by a list of jobs). In pseudo code:

CREATE or replace FUNCTION cron_jobs() RETURNS void LANGUAGE plpgsql AS $$
DECLARE
rec record;
BEGIN
/* update tbl1 every 15 minutes*/
select name, modified from job_last_update where name='tbl1' into rec;
if not found or rec.modified + interval '15 minutes' < now() then
perform tbl1_job();
update job_last_update set modified=now() where name='tbl1';
end if;

/* update tbl2 every 2 hours */
select name, modified from job_last_update where name='tbl2' into rec;
if not found or rec.modified + interval '2 hours' < now() then
perform tbl2_job();
update job_last_update set modified=now() where name='tbl2';
end if;

/* etc, etc.*/
END;
$$;

The 'job_last_update' table holds the last time a job was completed.

Is this a good way to do it?

Thanks,