Re: Why do index access methods use LP_DELETE?

Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> > Why do index access methods use LP_DELETE?
>
> My recollection is that I deliberately used LP_DELETE for the
> known-dead-tuple marker so that there couldn't be any confusion with
> the use of LP_USED. AFAIR, LP_USED isn't actually used in indexes,
> so we could do it differently if there were another possible use for
> the flag bit ... have you got one in mind?

Thanks. I understood there is little difference
between non-LP_USED and LP_DELETE for indexes.

I'm thinking to use LP_DELETE for relation tuples for incremental vacuum,
which is discussed in
http://archives.postgresql.org/pgsql-hackers/2005-03/msg00518.php
I'll try to mark tuples with LP_DELETE on visibility checking and
recycle the pages by bgwriter.
...However it is still a stage of an idea.

---
ITAGAKI Takahiro
NTT Cyber Space Laboratories