Jan Wieck wrote:
> On 6/25/2006 10:12 PM, Bruce Momjian wrote:
> >When you are using the update chaining, you can't mark that index row as
> >dead because it actually points to more than one row on the page, some
> >are non-visible, some are visible.
>
> Back up the truck ... you mean in the curre
On 6/25/2006 10:12 PM, Bruce Momjian wrote:
When you are using the update chaining, you can't mark that index row as
dead because it actually points to more than one row on the page, some
are non-visible, some are visible.
Back up the truck ... you mean in the current code base we have heap
tu
Jan Wieck wrote:
> > [item1]...[tuple1]
> >
> > becomes on UPDATE:
> >-->
> > [item1]...[tuple1][tuple2]
> > ->
> >
> > on another UPDATE, if tuple1 is no longer visible:
> >
> >-->
> > [item1]...[tuple1][tuple
On 6/25/2006 5:18 PM, Bruce Momjian wrote:
Jan Wieck wrote:
>> An update that results in all the same values of every indexed column of
>> a known deleted invisible tuple. This reused tuple can by definition not
>> be the one currently updated. So unless it is a table without a primary
>> key
bruce wrote:
> Why three? I explained using only two heap tuples:
>
> [item1]...[tuple1]
>
> becomes on UPDATE:
>-->
> [item1]...[tuple1][tuple2]
> ->
>
> on another UPDATE, if tuple1 is no longer visible:
>
>---
Luke,
> Other DBMS have index organized tables that can use either hash or btree
> organizations, both of which have their uses. We are planning to
> implement btree organized tables sometime - anyone else interested in
> this idea?
Search the archives. It's been dicussed on this list at least
Dawid,
> Other idea than using histogram_bounds would be using the
> position of key inside the index to determine the "ideal"
> place of row inside the table and find the closest free spot
> there. This would be of course much more precise and wouldn't
> rely on statistic.
This is generally
There is a well known command called CLUSTER which organizes tablein specified index's order. It has a drawback, that new tuples added arenot in this order. Last night I had idea which could be interesting, I hope.
The idea is to make use of 'histogram_bounds' collected statistical data.Instead of
Alright, I'm working on a fast prototype using the SRF.On 6/23/06, Simon Riggs <[EMAIL PROTECTED]> wrote:
On Fri, 2006-06-23 at 10:59 -0300, Diogo Biazus wrote:> On 6/23/06, Simon Riggs <
[EMAIL PROTECTED]> wrote:> > - give more flexibility for managing the xlogs remotely>> Not sure
Hannu Krosing wrote:
> ?hel kenal p?eval, P, 2006-06-25 kell 14:24, kirjutas Bruce Momjian:
> > Jan Wieck wrote:
> > > >> Sure, but index reuse seems a lot easier, as there is nothing
> > > >> additional
> > > >> to remember or clean out when doing it.
> > > >
> > > > Yes, seems so. TODO added:
Jan Wieck wrote:
> >> An update that results in all the same values of every indexed column of
> >> a known deleted invisible tuple. This reused tuple can by definition not
> >> be the one currently updated. So unless it is a table without a primary
> >> key, this assumes that at least 3 version
Ühel kenal päeval, P, 2006-06-25 kell 06:52, kirjutas Mark Woodward:
> I'm not sure why vacuum can't run similarly to the way it does now.
What do you mean ?
Currently vacuum runs a three-step process
1) runs a full scan over heap and collects all dead tuple ctids from
heap
2) run full scans o
Ühel kenal päeval, P, 2006-06-25 kell 14:24, kirjutas Bruce Momjian:
> Jan Wieck wrote:
> > >> Sure, but index reuse seems a lot easier, as there is nothing additional
> > >> to remember or clean out when doing it.
> > >
> > > Yes, seems so. TODO added:
> > >
> > > * Reuse index tuples that po
On 6/25/2006 2:24 PM, Bruce Momjian wrote:
Jan Wieck wrote:
>> Sure, but index reuse seems a lot easier, as there is nothing additional
>> to remember or clean out when doing it.
>
> Yes, seems so. TODO added:
>
> * Reuse index tuples that point to heap tuples that are not visible to
>
Heikki Linnakangas wrote:
> On Sat, 24 Jun 2006, Bruce Momjian wrote:
>
> > Because having them be on the same page is the only way you can update
> > the page item pointer so when you recycle the row, you the indexes are
> > now pointing to the new version. Pages look like:
> >
> > [marker][
Jan Wieck wrote:
> >> Sure, but index reuse seems a lot easier, as there is nothing additional
> >> to remember or clean out when doing it.
> >
> > Yes, seems so. TODO added:
> >
> > * Reuse index tuples that point to heap tuples that are not visible to
> > anyone?
> >
> >> When reusi
On Sat, 24 Jun 2006, Bruce Momjian wrote:
Because having them be on the same page is the only way you can update
the page item pointer so when you recycle the row, you the indexes are
now pointing to the new version. Pages look like:
[marker][item1][item2][item3]...[tuple1][tuple2][tup
On 6/24/2006 4:10 PM, Hannu Krosing wrote:
Ühel kenal päeval, L, 2006-06-24 kell 15:44, kirjutas Jan Wieck:
>> That fixes the symptom, not the problem. The problem is performance
>> steadily degrades over time.
>
> No, you got it backwards. The performance degradation is the symptom.
> The
On 6/25/2006 12:27 PM, Bruce Momjian wrote:
Hannu Krosing wrote:
> > Maybe we could start from reusing the index tuples which point to
> > invisible tuples ? The index is not MVCC anyway, so maybe it is easier
> > to do in-place replacement there ?
> >
> > This probably has the same obstacles
On 6/25/2006 6:52 AM, Mark Woodward wrote:
On 6/24/2006 9:23 AM, Mark Woodward wrote:
On Sat, 24 Jun 2006, Mark Woodward wrote:
I'm probably mistaken, but aren't there already forward references in
tuples to later versions? If so, I'm only sugesting reversing the
order
and referencing the lat
On 6/24/06, Mark Woodward <[EMAIL PROTECTED]> wrote:
I originally suggested a methodology for preserving MVCC and everyone is
confusing it as update "in place," this isnot what I intended.
Actually, you should've presented your idea as performing MVCC the way
Firebird does... the idea is basica
Hannu Krosing wrote:
> > > Maybe we could start from reusing the index tuples which point to
> > > invisible tuples ? The index is not MVCC anyway, so maybe it is easier
> > > to do in-place replacement there ?
> > >
> > > This probably has the same obstacles which have prevented us from
> > > rem
Hi Álvaro, Thank you about your answer. I thought that Postgres could management the space for outer and inner tables. Because, some articles has showed how this make the difference. Alvaro please, And about count of pages that postgres read on query i
> On 6/24/2006 9:23 AM, Mark Woodward wrote:
>
>>> On Sat, 24 Jun 2006, Mark Woodward wrote:
>>>
I'm probably mistaken, but aren't there already forward references in
tuples to later versions? If so, I'm only sugesting reversing the
order
and referencing the latest version.
>>>
On Sat, Jun 24, 2006 at 09:45:45PM -0400, Bruce Momjian wrote:
> Michael, I saw your patch stating that the copyright was assigned to
> PGDG. However, once that happens, we are of the policy to remove
> copyrights to individual users because it confuses things.
>
> Therefore, I have updated your
25 matches
Mail list logo
