Re: [HACKERS] Optimize postgres protocol for fixed size arrays

On Tue, Nov 22, 2011 at 6:52 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Oliver Jowett <oliver@opencloud.com> writes:
>> On 23 November 2011 10:47, Mikko Tiihonen
>> <mikko.tiihonen@nitorcreations.com> wrote:
>>> Here is a patch that adds a new flag to the protocol that is set when all
>>> elements of the array are of same fixed size.
>
>> How does a client detect that this feature is supported?
>
> The only way that anything like this will go in is as part of a protocol
> version bump, so discoverability would reduce to knowing which protocol
> you're using.  We should file this away as one of the things we might
> want to do whenever there's sufficient critical mass for a new wire
> protocol version.
>
> Note that COPY BINARY files would be affected too, and so we'd want to
> make sure that this sort of change is recognizable from a binary file's
> header.

Wire format changes can only be made with a protocol version bump?  Is
this a new policy? In the past they were just made...for example the
money type was bumped to 64 bits.  In the past it was always buyer
beware for binary format consumers.

merlin