Total Homeostaticity and Integrity Constraints Restorability Recognition
نویسندگان
چکیده
We introduce and explore a property of deductive data bases with updates wich we call total homeostaticity, and which substantially generalizes the following their property: ”for any given external update violating the integrity constraints there exists a reaction of the data base, which restores the integrity constraints”. This property is characteristic of active data bases. We explore the computational complexity of total homeostaticity recognition in various subclasses of Datalog programs with updates and show that it is much simpler than the homeostaticity in a specific DB state. In particular, it turns out to be polynomial time solvable in several situations of interest for
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تاریخ انتشار 1997