Re: HOT for PostgreSQL 8.3

On Mon, Feb 12, 2007 at 12:48:06AM -0500, Tom Lane wrote:
> Hannu Krosing <hannu@skype.net> writes:
> > How about adding a new 2-byte field to header for in-page c_tid poiner
> > for HOT ?
> We just finished sweating blood to get the tuple header size down to 23
> bytes from 27 (which saves 8 bytes not 4 if MAXALIGN=8).  We are not
> going to blow that again on HOT.

I haven't had enough time to follow all of the details here - but if the
ability to update a row with minimal overhead, as long as there is extra
room in the same block is a great idea (it sounds appealing to me) - could
it be done with just a 1 byte list? 24 instead of 23 for the tuple size.

I'll try to catch up at some point. :-)

Cheers,
mark

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