Re: pg_upgrade: What is changed?

On Wed, Aug 23, 2006 at 10:26:19AM +0200, Zdenek Kotala wrote:

<snip>

> 1) BKI - catalog.
> c) Some records are changed
> action: ???

They just need to be changed. In principle the datalog needs to be
updated so it looks like a database initdb'd with the new version.

> 5) Tuples
> question: Does have data types some disk representation?
> Does have tupleheader same structure?

I think only the inet/cidr types changed format this release. Ways to
handle that have been discussed:

1. Have server contain code for old versions under old OID. This was
mentioned as a possibility.
2. ALTER TYPE ALTER TYPE from old to new type, possibly using text as
intermediary.
3. Fiddle with bits on disk (not sure if this is even possible)

> 6) Indexes
> question: Any changes on disk representation?
> Should be possible remove all index before upgrade and
> recreate them on the new version instead upgrade index structure?

Maybe, maybe not. Why risk it? Just REINDEX the whole database
afterwards.

> 8) WAL/XLOG
> Question: Should be deleted?

I imagine you should probably force a checkpoint and then wipe the wal
records. The WAL isn't going to be able to cover some of the stuff done
during the upgrade, so it'd be useless after anyway.

Hope this helps,
--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> From each according to his ability. To each according to his ability to litigate.