RE: Scan by TID (was RE: [HACKERS] How to add a new build-in operator)

> -----Original Message-----
> From: Bruce Momjian [mailto:maillist@candle.pha.pa.us]
> Sent: Tuesday, October 12, 1999 4:14 AM
> To: Tom Lane
> Cc: Hiroshi Inoue; pgsql-hackers
> Subject: Re: Scan by TID (was RE: [HACKERS] How to add a new build-in
> operator)
> 
> 
> > "Hiroshi Inoue" <Inoue@tpf.co.jp> writes:
> > > Yes,I have done a part of my story.
> > > I would add new type of path and scan by which we are able to access
> > > tids directly.
> > 
> > Yes, new path type, new plan type, probably a new access method if
> > you want to keep things clean in the executor, cost-estimation routines
> > in the planner, etc. etc.
> > 
> > Looks like a lot of work, and a lot of added code bulk that will
> > have to be maintained.  I haven't figured out why you think it's
> > worth it... tids are so transient that I don't see much need for
> > finding tuples by them...
> 
> That's why I just suggested a more short-circuited option of snatching
> tid oids from expressions, and doing a heap_fetch directly at that point
> to avoid the index scan.  Seems it could be done in just one file.
>

I have thought the way as Tom says and I have a prospect to do it.
But it would take a lot of work.

Where to snatch and return to(or exit from) planner/executor 
in your story ?

Hiroshi Inoue
Inoue@tpf.co.jp.