"Rob Brucks" <rob(dot)brucks(at)rackspace(dot)com> writes:
> The user's permissions need to be checked before requesting an exclusive
> lock on the table for the alter.
Unfortunately, that cure is as bad or worse than the disease. It's not
possible to do a permissions check before acquiring any lock --- what if
somebody is changing the permissions under you, or even dropping or
renaming the table? We could acquire sharelock, do the permissions
check, and then upgrade to exclusive lock; but lock upgrading has its
own unpleasant consequences, notably increased risk of deadlock.
So it's unlikely this is going to get changed.
regards, tom lane