From: | Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> |
---|---|
To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | Hannu Krosing <hannu(at)tm(dot)ee>, Curtis Faith <curtis(at)galtcapital(dot)com>, pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: Brain dump: btree collapsing |
Date: | 2003-02-13 23:18:16 |
Message-ID: | 200302132318.h1DNIGt28322@candle.pha.pa.us |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Tom Lane wrote:
> Hannu Krosing <hannu(at)tm(dot)ee> writes:
> > But if we would allow the scans to find the same keys twice without ill
> > effects (as was suggested earlier, for using btrees to index arrays),
>
> How is returning the same data twice not an "ill effect"?
>
> > then we could possibly 1) copy the key to the right 2) wait for all
> > right-to-left scans that have fallen between old and new values to pass
> > and only then 3) delete the "old left" key.
>
> How will you wait for scans that you know nothing of to go past?
> Especially when they are going to be blocked by your own write lock
> on the left page?
I think we should skip any pages where we can't get a lock.
--
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073
From | Date | Subject | |
---|---|---|---|
Next Message | mlw | 2003-02-13 23:25:20 | Re: location of the configuration files |
Previous Message | Tom Lane | 2003-02-13 23:13:55 | Re: Brain dump: btree collapsing |