Re: Postgres architecture for multiple instances

"Daniel Verite" <daniel@manitou-mail.org> writes:
>     Giuseppe Sacco wrote:
>> Another important fact is about large objects, if you happen to use
>> them: their OID is not just unique to the database, but to the whole
>> cluster. This means that when you move a database in a cluster from a
>> production system to a database on a test cluster, you may get errors
>> when same OID already exists in target cluster (even if it is used in a
>> different database).

> Well, I'm doing this frequently and it doesn't cause any error.

That's because the above claim is nonsense.  pg_largeobject is not shared
across databases of a cluster.

You could well have collisions against large objects in the same database,
though, if you're adding more large objects to an existing database and
expecting to preserve their OIDs.

            regards, tom lane