First-order queries on databases embedded in an infinite structure
نویسندگان
چکیده
منابع مشابه
First-Order Queries on Databases Embedded in an Infinite Structure
We consider generic isomorphism invariant queries on rela tional databases embedded in an in nite background structure As sume a generic query is expressible by a rst order formula over the embedded domain that may involve both the relations of the database and the relations and functions of the background structure Then this query is already expressible by a rst order formula involving just an...
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ژورنال
عنوان ژورنال: Information Processing Letters
سال: 1996
ISSN: 0020-0190
DOI: 10.1016/s0020-0190(96)00140-8