Re: Where to find information on the new HOT tables?

Alvaro Herrera wrote:
> Bruce Momjian escribi?:
> > Dimitri Fontaine wrote:
>
> > > What about Alvaro's concern about manual vacuuming policies editing wrt to
> > > HOT?
> >
> > I think most people will be using autovacuum, and those who aren't will
> > have to realize that HOT makes vacuuming less needed.
>
> Hmm, and how will they realize it, if they don't understand how HOT
> comes into the equation?

Well, since this is a change in the behavior of this release, and not
something that will change over time, perhaps we need a sentence in
there about vacuuming changes.

The release note item says we can now reclaim without vacuum:

"UPDATE"s and "DELETE"s leave dead tuples behind, as do failed
"INSERT"s. Previously only "VACUUM" could reclaim
space taken by dead tuples. With HOT dead tuple space can be
automatically reclaimed at the time of "INSERT" or ...

so it seems logical that the need to vacuum would change. We can add
an explicit sentence about that to the release notes.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://postgres.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +