Re: PostgreSQL Limits: maximum number of columns in SELECT result - Mailing list pgsql-hackers

From Dave Cramer
Subject Re: PostgreSQL Limits: maximum number of columns in SELECT result
Date
Msg-id CADK3HH+zsL5bEPv7i8dOEgGm1D4k7b6RmmVUqL9VgqbFnihoPg@mail.gmail.com
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In response to Re: PostgreSQL Limits: maximum number of columns in SELECT result  (Dave Cramer <davecramer@postgres.rocks>)
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On Tue, 31 May 2022 at 09:56, Amul Sul <sulamul@gmail.com> wrote:
On Tue, May 31, 2022 at 12:46 PM Vladimir Sitnikov
<sitnikov.vladimir@gmail.com> wrote:
>
> Hi,
>
> Today I hit "ERROR: target lists can have at most 1664 entries", and I was surprised the limit was not documented.
>
> I suggest that the limit of "1664 columns per tuple" (or whatever is the right term) should be added
> to the list at https://www.postgresql.org/docs/current/limits.html e.g. after "columns per table".
>

Rather, I think the "columns per table" limit needs to be updated to 1664.

Actually that is correct. Columns per table is MaxHeapAttributeNumber which is 1600.

MaxTupleAttributeNumber  is 1664  and is the limit of user columns in a tuple.

Dave

Attached is a patch to limits.sgml. I'm not sure this is where it belongs, as it's not a physical limit per-se but I am not familiar enough with the docs to propose another location.

Note this was suggested by Vladimir.

see attached  
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