| From: | Peter Geoghegan <pg(at)bowt(dot)ie> |
|---|---|
| To: | Claudio Freire <klaussfreire(at)gmail(dot)com> |
| Cc: | Robert Haas <robertmhaas(at)gmail(dot)com>, PostgreSQL-Dev <pgsql-hackers(at)postgresql(dot)org>, Andres Freund <andres(at)anarazel(dot)de> |
| Subject: | Re: [WIP] [B-Tree] Keep indexes sorted by heap physical location |
| Date: | 2017-07-24 17:02:45 |
| Message-ID: | CAH2-Wzn4s7hdMD_69gwFW3ER0FsPLgFbqtvJXH9Rf+tQNC2xHA@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Mon, Jul 24, 2017 at 9:51 AM, Claudio Freire <klaussfreire(at)gmail(dot)com> wrote:
> My point was that the TID doesn't have to point to an actual tuple.
>
> It's more of a keyspace thing, so it doesn't need to match real
> tuples, it can just divide the keyspace with an arbitrary cutoff, and
> should be cheapter to maintain without that requirement.
I agree, but unless you're using normalized keys, then I don't see
that you get much useful leeway from using fake or truncated TID
values. Presumably the comparison logic will be based on comparing an
ItemPointerData field, which is impractical to truncate.
--
Peter Geoghegan
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Sokolov Yura | 2017-07-24 17:10:48 | Re: Increase Vacuum ring buffer. |
| Previous Message | Claudio Freire | 2017-07-24 16:51:19 | Re: [WIP] [B-Tree] Keep indexes sorted by heap physical location |