Re: LISTEN considered dangerous

In article <44D0478D.3060201@partyticket.net>,
Flemming Frandsen <ff@partyticket.net> writes:

>> I would still expect any
>> reimplementation of notify messaging to honor the principle that a
>> LISTEN doesn't take effect till you commit.

> Naturally, the listen should not do anything at all when followed by a
> rollback.

> However if you start listening in a transaction then you should get
> all events that have happened after the snapshot that the transaction
> represents (the start of the transaction).

Here you're contradicting yourself.  In your second paragraph you
state that LISTEN should get events unless later cancelled by a
ROLLBACK.  How should LISTEN know if its transaction will commit or
abort?