Re: [HACKERS] Re: protocol version negotiation (Re: LibpqPGRES_COPY_BOTH - version compatibility)

Okay, I will add a mechanism to try connecting with 3.0 if 3.1 fails- that should be a few lines of code fe-connect.c;
thiswill eliminate the need for a back-patch. What do you think of the rest of the change? 
 

Thanks,
Badrul

-----Original Message-----
From: Robert Haas [mailto:robertmhaas@gmail.com] 
Sent: Wednesday, October 4, 2017 4:54 AM
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Badrul Chowdhury <bachow@microsoft.com>; Satyanarayana Narlapuram <Satyanarayana.Narlapuram@microsoft.com>; Craig
Ringer<craig@2ndquadrant.com>; Peter Eisentraut <peter_e@gmx.net>; Magnus Hagander <magnus@hagander.net>;
PostgreSQL-development<pgsql-hackers@postgresql.org>
 
Subject: Re: [HACKERS] Re: protocol version negotiation (Re: Libpq PGRES_COPY_BOTH - version compatibility)

On Tue, Oct 3, 2017 at 9:46 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Badrul Chowdhury <bachow@microsoft.com> writes:
>> 1. Pgwire protocol v3.0 with negotiation is called v3.1.
>> 2. There are 2 patches for the change: a BE-specific patch that will be backported and a FE-specific patch that is
onlyfor pg10 and above.
 
>
> TBH, anything that presupposes a backported change in the backend is 
> broken by definition.  We expect libpq to be able to connect to older 
> servers, and that has to include servers that didn't get this memo.
>
> It would be all right for libpq to make a second connection attempt if 
> its first one fails, as we did in the 2.0 -> 3.0 change.

Hmm, that's another approach, but I prefer the one advocated by Tom Lane.


https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.postgresql.org%2Fmessage-id%2F30788.1498672033%40sss.pgh.pa.us&data=02%7C01%7Cbachow%40microsoft.com%7Cd183fe16a3a445f4bc7c08d50b1e9e9e%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636427148510331370&sdata=jLwhk6twUrlsm9K6yLronVvg%2Fjx93MM37UXm6NndfLY%3D&reserved=0

https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.postgresql.org%2Fmessage-id%2F24357.1498703265%2540sss.pgh.pa.us&data=02%7C01%7Cbachow%40microsoft.com%7Cd183fe16a3a445f4bc7c08d50b1e9e9e%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636427148510331370&sdata=gtFfNcxR3qK7rzieQQ0EAOFn%2BsDsw8rjtQeWwyIv6EY%3D&reserved=0

--
Robert Haas
EnterpriseDB:
https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.enterprisedb.com&data=02%7C01%7Cbachow%40microsoft.com%7Cd183fe16a3a445f4bc7c08d50b1e9e9e%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636427148510331370&sdata=wf9cTkQEnRzkdaZxZ1D6NBY9kZbiViyni5lkA7nzEXM%3D&reserved=0
The Enterprise PostgreSQL Company

--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers