Re: triggers on prepare, commit, rollback... ?

Fabien COELHO <coelho@cri.ensmp.fr> writes:
> I've played with triggers a bit, and I have noticed that there seem to be 
> no way to add a trigger on events such as "prepare", "commit", "rollback", 
> "savepoint",

Yup, and there won't be.  This has been suggested and rejected before.
See the archives.

> It seems to me that such triggers would be useful to help implement a 
> "simple" (hmmm...) synchroneous replication system,

That argument has no credibility whatever.  We have not even been able
to get the replication projects to agree on a common set of custom
hooks; the chance that they could get by with triggers on SQL-visible
events is nil.
        regards, tom lane