Re: Fast default stuff versus pg_upgrade

On 06/21/2018 01:18 PM, Tom Lane wrote:
> Andrew Dunstan <andrew.dunstan@2ndquadrant.com> writes:
>> On 06/21/2018 12:39 PM, Tom Lane wrote:
>>> Andres Freund <andres@anarazel.de> writes:
>> On June 21, 2018 9:04:28 AM PDT, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> This isn't really ready to go.  One clear problem is that you broke
>> pg_dump'ing from any pre-v11 version, because you did not add suitable
>> null outputs to the pre-v11 query variants in getTableAttrs.
>> I followed the pattern used for attidentity. But why will it spit out
>> warnings? It doesn't ask for the missing stuff from an older version.
> Oh, I see.  Well, the short answer is that that's not the style we use
> in pg_dump, and the attidentity code is inappropriate/wrong too IMO.
> When something has been done one way a hundred times before, thinking
> you're too smart for that and you'll do it some other way does not lend
> itself to code clarity or reviewability.
>
> I might be OK with a patch that converts *all* of pg_dump's cross-version
> difference handling code to depend on PQfnumber silently returning -1
> rather than failing, but I don't want to see it done like that in just
> one or two places.
>
>     


I don't mind changing it. But please note that I wouldn't have done it 
that way unless there were a precedent. I fully expected to add dummy 
values to all the previous queries, but when I couldn't find attidentity 
in them to put them next to I followed that example.

I don't think it's at all a bad idea, TBH. It means you only have to add 
one query per version rather than having to adjust all of them.

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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