Re: COPY enhancements

On Sat, 12 Sep 2009, Tom Lane wrote:

> Everybody in the world is going to want their own little problem to be 
> handled in the fast path.  And soon it won't be so fast anymore.  I 
> think it is perfectly reasonable to insist that the fast path is only 
> for "clean" data import.

The extra overhead is that when you hit the checks that are already in the 
code, where the row would normally be rejected, there's a second check as 
to whether that particular problem is considered OK or not.  There won't 
be any additional overhead for clean imports.  As I was pointing out in 
one of the messages in this thread, all of the expensive things you need 
are already being done.

As for "everybody in the world" wanting a specific fix for their private 
problems, I assure that everything I suggested comes up constantly on 
every legacy data conversion or import job I see.  This is not stuff that 
fits a one-off need, these are things that make it harder for people to 
adopt PostgreSQL all the time.  I wouldn't care about this one bit if 
these particular issues didn't ruin my day constantly.  Consider the fact 
that we're looking at three samples of people who have either already 
written a patch in this area or considered writing one showing up just 
among people on the hackers list.  That should be hint as to how common 
these requests are.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD