Classification of annotation semirings over containment of conjunctive queries
We study the problem of query containment of conjunctive queries over annotated databases. Annotations are typically attached to tuples and represent metadata, such as probability, multiplicity, comments, or provenance. It is usually assumed that annotations are drawn from a commutative semiring. Su...
Những tác giả chính: | , , |
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Định dạng: | Journal article |
Được phát hành: |
Association for Computing Machinery
2017
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