Re: reserving space in a rec for future update

On Nov 14, 2007, at 10:44 AM, Mike Charnoky wrote:

> In this usage scenario, doesn't the new HOT (heap only tuples) feature
> of PG8.3 help, in terms of the DB requiring less VACUUM maintenance?
>
> I am similarly performing a huge number of inserts, followed by a huge
> number of updates to fill in a few null fields.  The data is
> indexed by
> insert time.  My problem is, selects using that index degrade over
> time
> as updates are performed, presumably because data is no longer ordered
> sequentially across pages after updates are performed.  I was hoping
> that HOT would help here and am actually installing PG8.3 now in order
> to perform some testing...
>
>
> Mike

Some, what HOT does is keeps index rows from being updated when
updates are made to column values that aren't indexed.  The same
insert/delete still happens in the table data.

Erik Jones

Software Developer | Emma®
erik@myemma.com
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