An ODBMS Approach to Persistency in CMS

Persistent object management has been always at the centre of the CMS Analysis and Reconstruction Framework ( CARF). Already the very first prototypes had an ODBMS database ( Objectivity/DB) as the key component. Today, Objectivity/DB is fully integrated into CARF. The present version of CARF offers persistent object management for event structure and meta-data. In particular it manages raw data from test-beams, simulated objects ( particles, hits and digis) and reconstructed objects common to test-beams and simulation. CARF is used for detector performance and high level trigger studies. A review of experiences will be presented.