Re: LISTEN considered dangerous

On Fri, 4 Aug 2006, Martijn van Oosterhout wrote:

> Really? Even pg_dump cares? Or your maintainence scripts
> (VACUUM/ANALYZE)?

Ok, those clients don't, but you rarely have many vacuum/pg_dump
processes going on at the same time, so storing the events for them and
throwing them away is not that big of a deal imho.


> I'd have to disagree though. In most of the systems I've worked with
> the database is in the center of the system. It'd be access by CGI
> scripts, cron job, batch jobs started by a person, load triggered by
> emails, etc. These may all use very different methods of accessing the
> database. Even if an application used LISTEN/NOTIFY, I can't imagine
> any bulk load/store being interested.

Hmm, maybe you are right:)

Maybe a new implementation should be able to do both.

That way you could set the timetravel option on the begin statement:
begin listen now

So transactions that like to get all events they listen for during the
transaction can and everybody else will get only events that happen after
they commit.