Re: [WIP] In-place upgrade

"Joshua D. Drake" <jd(at)commandprompt(dot)com> writes:

> Gregory Stark wrote:
>> "Robert Haas" <robertmhaas(at)gmail(dot)com> writes:
>
>> An old page which never goes away. New page formats are introduced for a
>> reason -- to support new features. An old page lying around indefinitely means
>> some pages can't support those new features. Just as an example, DBAs may be
>> surprised to find out that large swathes of their database are still not
>> protected by CRC checksums months or years after having upgraded to 8.4 (or
>> even 8.5 or 8.6 or ...). They would certainly want a way to ensure all their
>> data is upgraded.
>
> Then provide a manual mechanism to convert all pages?

The origin of this thread was the dispute over this claim:

1. You *will* need a function to convert a page from old format to new
format. We do want to get rid of the old format pages eventually, whether
it's during VACUUM, whenever a page is read in, or by using an extra
utility. And that process needs to online. Please speak up now if you
disagree with that.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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