Re: Postgres DB Migration from 8.3 to 9.1

On Sun, Oct 14, 2012 at 12:13:03AM +0000, Jasen Betts wrote:
> On 2012-10-12, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> > On Thu, Oct 11, 2012 at 07:38:07PM -0700, John R Pierce wrote:
> >> On 10/11/12 7:15 PM, Vishalakshi Navaneethakrishnan wrote:
> >> >We have our production environment database server in Postgres 8.3
> >> >version. we have planned to upgrade to lastest version 9.1. Dump
> >> >from 8.3 and restore in Postgres 9.1 takes more than 5 hours. Any
> >> >other quick method to upgrade from 8.3 to 9.1. We need to reduce
> >> >our downtime below 1 hour. Any Possibilities..?
> >>
> >>
> >> is it the dump or the restore taking the lions share of that time?
> >>
> >> I don't know if pg_upgrade supports 8.3, but that would be one
> >> approach. getting it setup to work correctly can require some
> >> tinkering, but once you have that sorted, you start with a base
> >> backup of the 8.3 file system, and pg_upgrade 'converts' it to the
> >> newer version. you need both runtimes setup side by side so either
> >> can be run as pg_upgrade will need to start the old version in order
> >> to dump its metadata catalogs prior to migrating the data files. if
> >> you put both data directories on the same file system, it can use
> >> hard linking to 'move' the datafiles.
> >
> > Upgrading with pg_upgrade from 8.3 is going to require 9.2 to be
> > compiled with --disable-integer-datetimes.
>
> Doesn't that depend on what the 8.3 is using? Eg. Debian has used
> integer datetimes since 8.1 (or earlier - 8.1 is the oldest I have
> at hand)
>
> If he is using float datetimes is that going to be discontinued
> sometime?

No one has mentioned removing the ability to do floating-point
timestamps.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +