From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
cc: pgsql-hackers@postgresql.org
Subject: Re: pg_dump / copy bugs with "big lines" ?
In-reply-to: <56D70458.2010006@2ndquadrant.com>
References: <10cb3300-67ab-4d3b-a930-7106d4dbac04@mm>
 <56D70458.2010006@2ndquadrant.com>
Comments: In-reply-to Tomas Vondra <tomas.vondra@2ndquadrant.com>
	message dated "Wed, 02 Mar 2016 16:18:48 +0100"
Date: Wed, 02 Mar 2016 10:23:13 -0500
Message-ID: <21331.1456932193@sss.pgh.pa.us>
Precedence: bulk
Sender: pgsql-hackers-owner@postgresql.org

Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
> On 03/02/2016 03:18 PM, Daniel Verite wrote:
>> However, getting it to the client with \copy big2 to 'file'
>> still produces the error in psql:
>> lost synchronization with server: got message type "d"
>> and leaves an empty file, so there are more problems to solve to
>> go beyond 2GB text per row.

> My guess is this is a problem at the protocol level - the 'd' message is 
> CopyData, and all the messages use int32 to define length. So if there's 
> a 2GB row, it's likely to overflow.

I'm too lazy to check the exact wording, but I don't think there's a hard
and fast promise in the protocol doc that one CopyData message == one row.
So we could probably subdivide a very wide line into multiple messages.

			regards, tom lane


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