Rod Taylor <rbt@zort.ca> writes:
> I think it would be a rare event to have more than one person changing
> the database structure at the same time.
I don't buy this assumption --- consider for example two clients
creating temp tables.
> Anyway, the index example is a
> bad example isn't it? It already takes an lock on pg_class which is
> just as global.
Au contraire; there is no exclusive lock needed at present.
regards, tom lane