PRIMA: archiving and querying historical data with evolving schemas

Schema evolution poses serious challenges in historical data management. Traditionally historical data have been archived either by (i) migrating them into the current schema version, providing an easy query interface, but compromising archival quality, or (ii) by maintaining them under the original schema version in which they first appeared, leading to a perfect archival quality, but also to a difficult query interface. In PRIMA system, we achieve the best of both approaches, by archiving historical data under the original schema version, while automatically adapting the user temporal queries to the relevant schema versions. The users are allowed to query the archive under a schema version of choice, letting the system to rewrite the queries to the (potentially many) involved schema versions in the past. Moreover, the system offers automatic documentation of the schema history, and allows to pose temporal queries over the metadata history itself. The proposed demonstration, highligh...

• Type: Conference
• Year: 2009
• Where: SIGMOD
• Authors: Hyun J. Moon, Carlo Curino, MyungWon Ham, Carlo Zaniolo
• Keywords: Current Schema Version, Database, Original Schema Version, Relevant Schema Versions, SIGMOD 2009