Schema Migration for BaBar’s Objectivity Federations
نویسندگان
چکیده
As any High Energy Physics experiment evolves, the understanding and requirements for the data objects that need to be stored will change. This paper discusses the criteria to which these changes must conform so that physicists can continue to run their analysis programs and how these criteria are satisfied in BaBar’s Objectivity Federations. The Objectivity product has a native system for managing changes. Having reviewed this system BaBar decided that this system was not appropriate for its needs. The reasons behind this decision will be discussed. Having made this decision BaBar has had to develop their own techniques for handling changes in the requirements of persistent objects. These techniques are presented along with a discussion of their benefits and drawbacks.
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