Objectivity Question

[Shigeki Misawa <misawa@bnl.gov>]

Hello all.

I've got an Objectivity question that hopefully someone can
answer. (This might have been discussed previously, but I don't see a
record of it.)

During actual running of the experiment, I see at least 3 places where
data bases will be created. The first is in the on-line systems where
calibration/configuration data bases are being created. The second is
in the DAQ system, where DB's are being created to index raw event
data. The third is in the RCF reconstruction cluster where DB's
containing reconstructed data are created.

Presumably the data created in all three places will be accessed by
analysis code at later stages of processing. This implies that all the
data bases need to be in the same federation, or at least in
federations with "compatible" schema.

Is the assumption being made that there will be a single federation
that will be accessible to all three systems that will be creating
db's ?

If yes, presumably FTO/DRO will be used and will "fix" any problems
that may result from a breakdown in communication between the various
partitions, yes ?

Assuming that the above is the plan, if there is a breakdown in
communication between RCF and the experiment, AFAIK, it appears that
the reconstruction process proceeds to stop, since the DAQ/On-line
systems will constitute the quorum. Am I missing something here ?

Along the same vein, I thought that having 3 separate federations
would solve this problem, and that I would use oocopydb and ooattachdb 
to transfer db's between federation's. But this doesn't work since the 
db OID is cast in stone. Is this "fixed" in Version 5 ?


Documents from BaBar mention this problem, although the doc is dated
Sept '97 so its possible that a workaround was found.

Any info/insight would be appreciated.

Thanks.


Shigeki Misawa