Re: Libpq PGRES_COPY_BOTH - version compatibility

On Sun, Mar 27, 2011 at 04:02, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On Sun, Mar 27, 2011 at 4:09 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On Mon, Jan 3, 2011 at 6:55 AM, Magnus Hagander <magnus(at)hagander(dot)net> wrote:
>>>> ISTM that the correct fix is to increment to protocol version number to
>>>> 3.1 and send PGRES_COPY_OUT if the client requests version 3.0.  That's
>>>> what the version numbers are for, no?
>>>
>>> In a way - yes. I assume we didn't do that because it's considered "internal".
>>>
>>> It still won't help in my situation though - I need to know what
>>> version of the libpq headers I have in order to even be able to
>>> *compile* the program. At runtime, I could check against the server
>>> version, and get around it.
>>
>> This is listed on the open items list as "raise protocol version
>> number", but the above discussion suggests both that this might be
>> unnecessary and that it might not solve Magnus's problem anyway.
>>
>> What do we want to do here?
>
> We add an option as to how the protocol behaves, with default as 3.0.
> Older clients will not know about the new option and so will not
> request it.
>
> Magnus gets his new functionality, nothing breaks.

No he doesn't. Not yet - it needs the version check that's added to
9.1 - but it would have been needed for 9.0. So in a similar situation
at the next release it would be fixed, but not here.

That doesn't mean we shouldn't do this (haven't reconsidered the whole
thread) - but it doesn't solve the issue I originally raised.

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/