I just updated the FAQ to suggest 32 as the header size (I am assuming
OID's and 4-byte alignment). I am also assuming 7.5 which will loose
the cmin/cmax compression.
---------------------------------------------------------------------------
Tom Lane wrote:
> Ian Barwick <barwick@gmail.com> writes:
> > There is a little info in the FAQ:
> > http://www.postgresql.org/docs/faqs/FAQ.html
> > particularly sections 4.6 and 4.14
>
> I think the calculation in section 4.6 is out of date --- it's been
> awhile since row headers were 36 bytes. The more correct number is
> between 24 and 32 bytes depending on whether you created the table
> WITH OIDS and whether your machine requires 4- or 8-byte alignment.
>
> regards, tom lane
>
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