Extending and Inferring Functional Dependencies in Schema Transformations: Extended Version
| dc.contributor.author | Qi HE | en_US |
| dc.contributor.author | Tok Wang LING | en_US |
| dc.date.accessioned | 2004-10-21T14:28:52Z | en_US |
| dc.date.accessioned | 2017-01-23T06:59:47Z | |
| dc.date.available | 2004-10-21T14:28:52Z | en_US |
| dc.date.available | 2017-01-23T06:59:47Z | |
| dc.date.issued | 2004-03-01T00:00:00Z | en_US |
| dc.description.abstract | Functional dependency (FD) plays an important role in individual databases. In this paper, we study FDs in the context of multi-database interoperability. A major challenge in the integration of heterogeneous database schemas is of schematic discrepancies, when the data (values) of one database correspond to metadata (schema labels) of another. We first study the schematic discrepant transformations, i.e., transformations between schematic discrepant schemas. We then define "restricted FD", an extension to conventional FD, to formalize some class of constraints in schematic discrepant databases, and give a complete set of inference rules of restricted FDs. Then we study the propagation of restricted FDs during schematic discrepant transformations. Algorithms are proposed to derive all the restricted FDs in transformed schemas from restricted FDs in original schemas. At last, we show some applications of restricted FDs in the context of multi-database interoperability: (1) use FDs to verify whether a SchemaSQL view is well-defined, (2) use FDs to normalize transformed(integrated) schemas, and so on. | en_US |
| dc.format.extent | 665080 bytes | en_US |
| dc.format.mimetype | application/pdf | en_US |
| dc.identifier.uri | https://dl.comp.nus.edu.sg/xmlui/handle/1900.100/1443 | en_US |
| dc.language.iso | en | en_US |
| dc.relation.ispartofseries | TRA3/04 | en_US |
| dc.title | Extending and Inferring Functional Dependencies in Schema Transformations: Extended Version | en_US |
| dc.type | Technical Report | en_US |