Journal of the ACM (JACM)
A Theory of Attributed Equivalence in Databases with Application to Schema Integration
IEEE Transactions on Software Engineering
Referential integrity revisited: an object-oriented perspective
Proceedings of the sixteenth international conference on Very large databases
The functional data model and the data languages DAPLEX
ACM Transactions on Database Systems (TODS)
Database description with SDM: a semantic database model
ACM Transactions on Database Systems (TODS)
Update semantics of relational views
ACM Transactions on Database Systems (TODS)
On the correct translation of update operations on relational views
ACM Transactions on Database Systems (TODS)
A language facility for designing database-intensive applications
ACM Transactions on Database Systems (TODS)
Canonical view update support through boolean algebras of components
PODS '84 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems
A Methodology for the Design and Transformation of Conceptual Schemas
VLDB '91 Proceedings of the 17th International Conference on Very Large Data Bases
The Use of Information Capacity in Schema Integration and Translation
VLDB '93 Proceedings of the 19th International Conference on Very Large Data Bases
Source integration for data warehousing
Multidimensional databases
Using full match classes for self-maintenance of mediated views
Enterprise information systems IV
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In this paper, we propose a methodology for schema integration where the semantics of updates is preserved during the view integration process. We propose to divide view integration into three steps: combination, restructuring, and optimization. In the view combination step, we define the combined schema that contains all original views, plus a new set of constraints that express how data in distinct views are interrelated. The restructuring step is devoted to normalizing the views so that merging becomes possible. The optimization step tries to reduce redundancy and the size of the schema. Our methodology defines a set of transformation primitives that allows schema integration to be realized in a safe (information preserving) and algorithmic way. In the proposed transformation primitives, the relationship between the original and transformed schema is formally specified by the instance and update mappings. We introduce the notion of an update semantics preserving transformation, which guarantees that the relationships between each view and the global schema, originated during the view integration process, reflect exactly the relationships between the views as defined by the combined schema. In our approach, the view definition mappings and the view update translator can be directly defined from the instance and update mappings between the different intermediate schemas generated during the view integration process.