Abstract
An algebraic foundation of database schema design is presented. A new database operator, namely, disaggregation, is introduced. Beginning with “free” families, repeated applications of disaggregation and three other operators (matching function, Cartesian product, and selection) yield families of increasingly elaborate structure. In particular, families defined by one join dependency and several “embedded” functional dependencies can be obtained in this manner.
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Index Terms
- Disaggregations in databases
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