Managing Database Incompleteness with the Guarded Fragment
نویسنده
چکیده
Traditional databases do not explicitly represent the portions over their schemas for which they are sound and complete. This paper proposes a method by which very fine grained meta-data descriptions may be attached to relational data sources to describe, among other things, the portions of various tables for which the database has complete data. Because of the formal properties of the meta-data description language, itself expressible within the guarded fragment of first-order logic, intensional descriptions of the coverage offered to a specific query may be generated. The techniques discussed in this paper are general and may apply to many scenarios where fine-grained meta-data descriptions are associated with tuple sets.
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