Re: Versioning policy and pg_upgrade

Thom Brown <thom@linux.com> writes:
> But I propose expanding it to read:

> "Major releases usually change the internal format of system tables
> and data files. These changes are often complex, so we don't maintain
> backward compatibility for data files. A dump/reload of the database
> cluster is required for major upgrades for upgrading from 8.2 or
> earlier.  For upgrading from version 8.3 and later, there is the
> option to use pg_upgrade (also known as pg_migrator prior to version
> 9.0), capable of in-place upgrades.  This means, for example, you can
> upgrade any minor version of 8.3 to 8.4 without having to perform a
> full backup and restore, resulting in a significantly faster upgrade."

> Too wordy?

I don't really think that pg_upgrade should be recommended for 8.3 to
8.4 upgrades.  There are too many limitations and it's not been well
tested.  I don't even trust it very much yet for 8.4 to 9.0 updates...
        regards, tom lane