Re: State of Beta 2 - Mailing list pgsql-general

From Manfred Koizar
Subject Re: State of Beta 2
Date
Msg-id 4jq3mvodqklpcblc1342mk650hrm1fclkl@email.aon.at
Whole thread Raw
In response to Re: State of Beta 2  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
On Fri, 12 Sep 2003 11:16:58 -0400, Tom Lane <tgl@sss.pgh.pa.us>
wrote:
>> This 1600 column limit has nothing to do with block size.
>
>Right, but that's not the only limit on number of columns.

I just wanted to make clear that increasing page size does not enable
you to get beyond that 1600 column limit.  This not so uncommon
misbelief is ... well, I wouldn't say caused, but at least not
contradicted by
http://www.postgresql.org/users-lounge/limitations.html

|   Maximum number of         250 - 1600 depending
|   columns in a table        on column types
| [...]
| The maximum table size and maximum number of columns can be
| increased if the default block size is increased to 32k.

>But raise the page size, and these
>limits increase, possibly allowing the 1600 number to become the actual
>limiting factor.

Theoretically with int2 or "char" columns the 1600 columns limit can
be reached even without changing the page size.  Figuring out a use
case for such a table is another story ...

Servus
 Manfred

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