[ZODB-Dev] Packless and copyTransactionsFrom()????

JohnD.Heintz JohnD.Heintz
Mon, 20 Aug 2001 13:31:27 -0500


Is export/import the only reason not to use them?

With the existense of copyTransactionFrom() and iterator() could it make=20
sense to rely on _p_oid?

Back before I understood BTrees I assumed that the only scalable way to a=
dd=20
millions of objects that I could then look up by ID was to use the databa=
se=20
generated IDs.  A little Oracle sequence dain bramage showing though.

John

On Monday 20 August 2001 12:52, Jim Fulton wrote:
> Christian Robottom Reis wrote:
> > On Mon, 20 Aug 2001, Jim Fulton wrote:
> > > > How do I do it while keeping the oids the same?  For better or wo=
rse
> > > > we are using the generated _p_oid like the primary key in RDMS-la=
nd.
> > >
> > > Bad bad bad. :)
> >
> > Bad as in "Don't do it if you still have a choice?" We've chosen to u=
se
> > an independent OID that we autogenerate, but I guess _p_oid's uniquen=
ess
> > is convenient.
>
> But persistent ids don't survive export and import.
> They should not be used as if they were meaningful,
> at the application level.
>
> Jim
>
> --
> Jim Fulton           mailto:jim@zope.com       Python Powered!
> Technical Director   (888) 344-4332            http://www.python.org
> Zope Corporation     http://www.zope.com       http://www.zope.org

--=20
=2E . . . . . . . . . . . . . . . . . . . . . . .

John D. Heintz | Senior Engineer

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