> > > Does looking up by the catalog keys take no cost ?
> >
> > Obviously there is cost, but doing a lookup only on demand, has got to be
> > cheaper in the long run than including the entire column definition in the
> > message whether it's wanted or not?
>
> So if there are 100 fields, should we ask the backend
> the column name 100 times ?
Also doesn't the planner/executor already have all needed info available ?
Thus answering from prepare would be a lot cheaper than selecting the descriptor
after prepare (more network roundtrips, parse, plan and execute the descriptor lookup).
If this where at the protocol level, the client could flag what info is wanted,
and thus avoid all unwanted overhead.
Andreas
