| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> |
| Cc: | Josh Berkus <josh(at)agliodbs(dot)com>, pgsql-hackers(at)postgresql(dot)org, Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>, ITAGAKI Takahiro <itagaki(dot)takahiro(at)lab(dot)ntt(dot)co(dot)jp> |
| Subject: | Re: Remove xmin and cmin from frozen tuples |
| Date: | 2005-09-02 21:16:09 |
| Message-ID: | 18130.1125695769@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> writes:
> On Fri, Sep 02, 2005 at 01:35:42PM -0700, Josh Berkus wrote:
>> Where I do see value is in enabling index-only access for "frozen" tables.
>> That would be a *huge* gain, especially with bitmaps. I think we've
>> discussed this before, though.
> That's a completely different discussion. Btree-organized heaps may
> help you there.
There was some talk of using a spare bit in index entries to mark "known
good" index entries (xmin committed and less than GlobalXmin, and xmax
invalid) but the cost of maintaining such bits seems nontrivial. In any
case I agree that's an independent issue.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Tom Lane | 2005-09-02 21:18:09 | Re: Remove xmin and cmin from frozen tuples |
| Previous Message | Matt Miller | 2005-09-02 21:09:01 | Re: Ora2Pg (was PL/pgSQL: EXCEPTION NOSAVEPOINT) |