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From Core Mnutes March 20, 2007:
ROOT data indexing: (Eric C.) ROOT-based metadata scheme (used by BABAR) containing pointers to locate all known data for a given event. The basic idea involves storing (File, Tree, Entry) in an external table, pointed to by a single pointer in an NTuple (index file), but with some additional flexibility (works with xrootd, including when data has been migrated to tape). Tools to read & copy the event data also provided. See https://confluence.slac.stanford.edu/download/attachments/20011/Event_Collections.pdf. BABAR code is all online in their CVS repository, module KanEvent. This scheme might find application in GLAST for interleave, skimming, and analysis scenarios.
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