First-Order Queries on Databases Embedded in an Infinite Structure
نویسندگان
چکیده
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 auxiliary linear ordering as background structure We present an elementary proof of this fact
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ورودعنوان ژورنال:
- Inf. Process. Lett.
دوره 60 شماره
صفحات -
تاریخ انتشار 1996