Re: PostgreSQL Limits and lack of documentation about them.

On 26 October 2018 at 11:40, Haribabu Kommi <kommi(dot)haribabu(at)gmail(dot)com> wrote:
> On Fri, Oct 26, 2018 at 9:30 AM David Rowley <david(dot)rowley(at)2ndquadrant(dot)com>
> wrote:
>>
>> For a long time, we documented our table size, max columns, max column
>> width limits, etc. in https://www.postgresql.org/about/ , but that
>> information seems to have now been removed. The last version I can
>> find with the information present is back in April this year. Here's a
>> link to what we had:
>>
>> https://web.archive.org/web/20180413232613/https://www.postgresql.org/about/
>>
>> I think it's a bit strange that we don't have this information fairly
>> early on in the official documentation. I only see a mention of the
>> 1600 column limit in the create table docs. Nothing central and don't
>> see mention of 32 TB table size limit.
>>
>> I don't have a patch, but I propose we include this information in the
>> docs, perhaps on a new page in the preface part of the documents.
>
>
> I also try to find such limits of PostgreSQL, but I couldn't find it.
> +1 to add them to docs.

I've attached a very rough patch which adds a new appendix section
named "Database Limitations". I've included what was mentioned in [1]
plus I've added a few other things that I thought should be mentioned.
I'm sure there will be many more ideas.

I'm not so sure about detailing limits of GUCs since the limits of
those are mentioned in pg_settings.

[1] https://web.archive.org/web/20180413232613/https://www.postgresql.org/about/

--
David Rowley http://www.2ndQuadrant.com/
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