Re: Restoring old database with OIDs that are now in use by another database after initdb = problems?

>
> I'm wondering what would happen if I were to backup/archive an old
> database with OIDs, then later someday, restore it after I've since done an
> initdb and there is someother database using the same OIDs as the old database.
> If I restore with OIDs, that would cause the OIDs to not be unique within
> the entire data directory.  Would PostgreSQL have any problems with this?  If
> PostgreSQL references all data by OID internally, then this would cause an OID
> to reference more than one object - a possible ambiquity?

Having duplicates in different tables really is not a problem.

>
> I'm trying to decide whether to use OIDs or sequences for unique ids.  I want
> to use the method that will work most reliably.  Trouble free backup and
> restore is very important.  OIDs look good since they are always there so they
> are simple and there's little you can do to misconfigure them.
> Serials/sequences might be better if I need sequential numbers but I don't
> really - just unique is good enough.  Again, I want to use what is simplest
> but more importantly, that stands the best chance of not being corrupted
> during backup/restore.
>

My book has a chapter on this:

    http://www.postgresql.org/docs/awbook.html


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