On 3/27/07, Bill Moran <wmoran at collaborativefusion.com> wrote:
> In response to Bill Moran <wmoran at collaborativefusion.com>:
>
> > The second thing that surprised me is an odd limit on the size of the node
> > ID.  As I already mentioned, we were trying to use node IDs that contain
> > some intelligence (serial # style), so our node IDs were around 20000000.
> > I didn't expect that to be a problem, since it's certainly small enough
> > to fit in an int, but slonik gave a rather cryptic error:
> > <stdin>:974: PGRES_FATAL_ERROR select "_clustername".initializeLocalNode(20000000, 'Local Slave node'); select "_clustername".enableNode_int(20000000);  - ERROR:  bigint out of range
> > CONTEXT:  SQL statement "SELECT  setval('"_clustername".sl_rowid_seq',  $1 ::int8 * '1000000000000000'::int8)"
> > PL/pgSQL function "initializelocalnode" line 26 at perform
> >
> > Which makes it appear as if the node ID is being multiplied by one
> > quadrillion before attempting to stuff it into a BIGINT.  when I set
> > the node ID down to single-digits, the error stopped.
>
> It appears as if this is happening to guarantee unique IDs for
> Slony-generated primary keys across all nodes.
>
> The thing is that it's only needed for tables that don't already have
> primary keys, and in that case it's rather arbitrary.  It's making the
> assumption that all the slony-generated primary keys on this node will
> never exceed 10^15.
>
> I'm kind up in the air about this.  I would like to put together a patch
> that will support longer node IDs, but 10^15 seems arbitrary, and anything
> I'd change it to would be arbitrary as well.  The painful thing is that in
> a database where all tables have primary keys, it's not needed anyway.
>
> I expect that not a lot of people are having trouble with this, or there
> would be more discussion about it up till now, but I'm curious if
> anyone has ideas to contribute.

Considering that people seem to agree that slony generated pkeys are
more of a wart than a feature, why not simply deprecate the feature
and remove it?

Andrew