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<TITLE>RE: [Slony1-general] replication through slony beween the nodes having different versions of postgres</TITLE>
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<P><FONT SIZE=2>Hi Greg<BR>
<BR>
Thanks for all your help :)<BR>
<BR>
Regards<BR>
Tamanna<BR>
<BR>
-----Original Message-----<BR>
From: Greg Sabino Mullane [<A HREF="mailto:greg@endpoint.com">mailto:greg@endpoint.com</A>]<BR>
Sent: Fri 7/23/2010 8:28 PM<BR>
To: tamanna madaan<BR>
Cc: slony1-general@lists.slony.info<BR>
Subject: Re: [Slony1-general] replication through slony beween the nodes having different versions of postgres<BR>
<BR>
> postgres-8.4.0 and 8.4.2 are completely compatible. Does it also mean that<BR>
> replication will work fine from postgres-8.4.0 to postgres-8.4.2 means<BR>
> from a lower to higher release. Does that holds true for postgres-8.4.4 as<BR>
> well ??<BR>
<BR>
Yes.<BR>
<BR>
> Moreover, in the release notes of 8.4.2 (link below), its mentioned that<BR>
> "A dump/restore is not required for those running 8.4.X unless you are having<BR>
> hash index" . Does that mean: if I am not using any hash index , then I<BR>
> can upgrade to postgres-8.4.2 from postgres-8.4.0 simply without any need of<BR>
> exporting my database schema and data in it before upgrading postgres and<BR>
> then importing it back after upgrade.<BR>
<BR>
Yes, that is correct. Going from one revision to another (where the last of the<BR>
three version number changes) never requires a dump and a reload. Even if you<BR>
have hash indexes, a dump and reload is not required, just a REINDEX after<BR>
the upgrade has completed.<BR>
<BR>
> won't it corrupt the data if I upgrade postgres db with my database<BR>
> schema/data in it ??<BR>
<BR>
No: the only thing that is changing is the Postgres program itself. The<BR>
underlying data is not changed, just the program that reads and writes<BR>
that data is slightly changed, to fix bugs.<BR>
<BR>
If I can further expound to this list some more best practices, you should<BR>
be subscribed to the pgsql-announce mailing list so you hear about new<BR>
released (of Postgres, Slony, and other Postgres-related programs). You<BR>
may also wish to run check_postgres.pl with the new_version_pg action,<BR>
which will give you a Nagios alert when your version of Postgres becomes<BR>
out of date.<BR>
<BR>
--<BR>
Greg Sabino Mullane greg@endpoint.com<BR>
End Point Corporation<BR>
PGP Key: 0x14964AC8<BR>
<BR>
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