The BABAR database: challenges, trends and projections

The BABAR database, based upon the Objectivity OO database management system, has been in production since early 1999. It has met its initial design requirements which were to accommodate a 100Hz event rate from the experiment at a scale of 200TB per year. However, with increased luminosity and changes in the physics requirements, these requirements have increased significantly for the current running period and will again increase in the future. New capabilities in the underlying ODBMS product, in particular those of multiple federation and read-only database support, have been incorporated into a new design that is backwards compatible with existing application code while offering scaling into the multi-petabyte size regime. Other optimizations, including the increased use of tightly coupled CORBA servers and an improved awareness of space inefficiencies, are also playing a part in meeting the new scaling requirements. The authors discuss these optimizations and the prospects for further scaling enhancements to address the longer-term needs of the experiment