Re: Practical error logging for very large COPY

On Mon, 2005-11-21 at 19:05 -0500, Tom Lane wrote:
> Simon Riggs <simon@2ndquadrant.com> writes:
> > Flow of control would be to:
> 
> >     locate page of index where value should go
> >     lock index block
> >     _bt_check_unique, but don't error
> >         if violation then insert row into ERRORTABLE
> >     else
> >         insert row into data block
> >         insert row into unique index
> >         unlock index block
> >         do other indexes
> 
> Ugh.  Do you realize how many levels of modularity violation are implied
> by that sketch?  

IMHO the above is fairly ugly, but I suggest it now because:
1. I want to avoid uniqueness violations in COPY
2. The logic used is very similar to that recently proposed for MERGE. 

If anybody has a better idea for (1), shout it out now.

If the logic is OK for MERGE, then it should be OK for COPY with
uniqeness violation trapping also. Both use uniqueness checking first,
so you'd need to argue against both or neither.

> Have you even thought about the fact that we have more
> than one kind of index?

Yes, but they don't support unique indexes do they?

Best Regards, Simon Riggs