Ron Mayer napsal(a):
Tom Lane wrote:
Another issue is that it might not be possible to update a page for
lack of space. Are we prepared to assume that there will never be a
transformation we need to apply that makes the data bigger? In such a
situation an in-place update might be impossible,
Bruce Momjian napsal(a):
Heikki Linnakangas wrote:
Zdenek Kotala wrote:
4) Implementation
The main point of implementation is to have several version of
PageHeader structure (e.g. PageHeader_04, PageHeader_03 ...) and correct
structure will be handled in special branch (see examples).
(this
Zdenek Kotala [EMAIL PROTECTED] writes:
It does not solve problems for example with TOAST tables. If chunks does not
fit
on a new page layout one of the chunk tuple have to be moved to free page. It
means you get a lot of pages with ~2kB of free unused space. And if max chunk
size is
Heikki Linnakangas wrote:
Zdenek Kotala wrote:
4) Implementation
The main point of implementation is to have several version of
PageHeader structure (e.g. PageHeader_04, PageHeader_03 ...) and correct
structure will be handled in special branch (see examples).
(this won't come as
On Jun 11, 2008, at 10:42 AM, Heikki Linnakangas wrote:
Another issue is that it might not be possible to update a page for
lack of space. Are we prepared to assume that there will never be a
transformation we need to apply that makes the data bigger?
We do need some solution to that. One
Tom Lane wrote:
Another issue is that it might not be possible to update a page for
lack of space. Are we prepared to assume that there will never be a
transformation we need to apply that makes the data bigger? In such a
situation an in-place update might be impossible, and that certainly
1) Overview
This proposal is part of inplace upgrade project. PostgreSQL should be able to
read any page in old version. This is basic for all possible upgrade method.
2) Background
We have several macros for manipulating of the page structures but this list is
not complete and many parts
Zdenek Kotala [EMAIL PROTECTED] writes:
There are examples:
void PageSetFull(Page page)
{
switch ( PageGetPageLayoutVersion(page) )
{
case 4 : ((PageHeader_04) (page))-pd_flags |= PD_PAGE_FULL;
break;
default
Zdenek Kotala wrote:
4) Implementation
The main point of implementation is to have several version of
PageHeader structure (e.g. PageHeader_04, PageHeader_03 ...) and correct
structure will be handled in special branch (see examples).
(this won't come as a surprise as we talked about this
Heikki Linnakangas [EMAIL PROTECTED] writes:
(this won't come as a surprise as we talked about this in PGCon, but) I
think we should rather convert the page structure to new format in
ReadBuffer the first time a page is read in. That would keep the changes
a lot more isolated.
The problem
Tom Lane napsal(a):
Zdenek Kotala [EMAIL PROTECTED] writes:
There are examples:
void PageSetFull(Page page)
{
switch ( PageGetPageLayoutVersion(page) )
{
case 4 : ((PageHeader_04) (page))-pd_flags |= PD_PAGE_FULL;
break;
Tom Lane wrote:
Heikki Linnakangas [EMAIL PROTECTED] writes:
(this won't come as a surprise as we talked about this in PGCon, but) I
think we should rather convert the page structure to new format in
ReadBuffer the first time a page is read in. That would keep the changes
a lot more isolated.
Heikki Linnakangas napsal(a):
Zdenek Kotala wrote:
4) Implementation
The main point of implementation is to have several version of
PageHeader structure (e.g. PageHeader_04, PageHeader_03 ...) and
correct structure will be handled in special branch (see examples).
(this won't come as a
Heikki Linnakangas napsal(a):
Tom Lane wrote:
Heikki Linnakangas [EMAIL PROTECTED] writes:
(this won't come as a surprise as we talked about this in PGCon, but)
I think we should rather convert the page structure to new format in
ReadBuffer the first time a page is read in. That would keep
Tom Lane [EMAIL PROTECTED] writes:
(Likely counterexample: adding collation info to text values.)
I don't think the argument really needs an example, but I would be pretty
upset if we proposed tagging every text datum with a collation. Encoding
perhaps, though that seems like a bad idea to me
Gregory Stark wrote:
Tom Lane [EMAIL PROTECTED] writes:
(Likely counterexample: adding collation info to text values.)
I don't think the argument really needs an example, but I
would be pretty
upset if we proposed tagging every text datum with a
collation. Encoding
perhaps, though
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