Grouper Developers Forum

[Tom Barton <>]

Jim,

The flattened table benefits replication of membership info into systems 
external to grouper. Without providing that flattened view, a change log 
consumer would need to calculate flattened membership for itself, and 
that has the possibility to produce inaccurate effects depending on when 
it does so. The flattened table supports a serialized change log that 
can be queried at any time to produce an accurate result.

I don't think anything internal to grouper depends on the flattened 
table. XMPP and HTTPS based change notifications depend on the flattened 
table. Ldappc-ng either does now or will with the next release.

Good luck with you implementation this summer! I'm very interested to 
hear how that goes, how things perform, and how it gets used.

Tom

Jim Fox wrote:
> Tom,
>
> Thanks for the new release.
>
> Our Grouper group registry is not yet live, but will be soon.
> It will replace the production system sometime this summer.
> I'd like to upgrade to 1.6 before that rather than afterward.
>
> The new "flattened memberships" table concerns me for a couple
> of reasons.  First, it requires the change log be enabled, which we
> don't do.  Second, it appears to contain a record for each effective
> member of each group.  Correct me if I'm wrong there.
>
> We already have over two million records in the 'direct membership'
> table, grouper_memberships.  We have many large groups (over 100K
> members) that are themselves members of many other groups.  I can
> see the flattened memberships table easily reaching 10 to 20 million
> records -- and to what point?  Most of the activity of the registry
> deals with direct membership, not effective membership.
>
> So my question is: What is the consequence of running without the
> change log, ignoring the flattened memberships table altogether?
> Are there any core functions of grouper that are going to depend
> on this table?