Re: An idea for parallelizing COPY within one backend

Tom Lane wrote:
> "Florian G. Pflug" <fgp(at)phlo(dot)org> writes:
>> ...
>> Neither the "dealer", nor the "workers" would need access to the either
>> the shared memory or the disk, thereby not messing with the "one backend
>> is one transaction is one session" dogma.
>> ...
>
> Unfortunately, this idea has far too narrow a view of what a datatype
> input function might do. Just for starters, consider "enum" input,
> which certainly requires catalog access. We have also explicitly
> acknowledged the idea that datatype I/O functions might try to store
> typmod-related data in some special catalog somewhere.

Hm... how many in-core datatypes are there which need catalog access in
their input or output functions? Maybe we could change the API for
i/o functions in a way that allows us to request all needed information
to be cached?

regards, Florian Pflug