Re: Data migration from postgres 8.4 to 9.4

On Mon, Apr 16, 2018 at 12:33 PM, Akshay Ballarpure <
akshay(dot)ballarpure(at)tcs(dot)com> wrote:

> Hello,
> I need help in using postgresql 8.4 data in postgres 9.4 version. Do I
> need to run any tool to achieve the same?
>
> Steps i followed is ran postgresql 8.4 and 9.4, copied data from 8.4
> instance to 9.4 and try to start postgresql 9.4 but no luck, getting below
> error.
>
> [root(at)ms-esmon esm-data]# su - postgres -c "/opt/rh/rh-postgresql94/root/usr/bin/postgres
> -D /var/ericsson/esm-data/postgresql-data/ 2>&1 &"
> [root(at)ms-esmon esm-data]# LOG: skipping missing configuration file
> "/var/ericsson/esm-data/postgresql-data/postgresql.auto.conf"
> 2018-04-16 06:52:01.546 GMT *FATAL*: database files are incompatible
> with server
> 2018-04-16 06:52:01.546 GMT *DETAIL*: The data directory was
> initialized by PostgreSQL version 8.4, which is not compatible with this
> version 9.4.9.
>
>
> With Best Regards
> Akshay
> Ericsson OSS MON
> Tata Consultancy Services
> Mailto: akshay(dot)ballarpure(at)tcs(dot)com
> Website: http://www.tcs.com

You cannot simply copy data between major versions. Look into pg_upgrade
utility to upgrade your database, or you could use pg_dump/pg_restore to
migrate between major versions.

Amitabh