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Title: Execution model for limited ambiguity rules and its application to derived data update

Journal Article · · ACM Transactions on Database Systems
 [1];  [2];  [3]
  1. Lawrence Berkeley National Lab., CA (United States)
  2. Univ. of Colorado, Boulder, CO (United States)
  3. Univ. of Southern California, Los Angeles, CA (United States)

A novel execution model for rule application in active databases is developed and applied to the problem of updating derived data in a database represented using a semantic, object-based database model. The execution model is based on the use of `limited ambiguity rules` (LARs), which permit disjunction in rule actions. The execution model essentially performs a breadth-first exploration of alternative extensions of a user-requested update. Given an object-based database scheme, both integrity constraints and specifications of derived classes and attributes are compiled into a family of limited ambiguity rules. A theoretical analysis shows that the approach is sound: the execution model returns all valid `completions` of a user-requested update, or terminates with an appropriate error notification. The complexity of the approach in connection with derived data update is considered. 42 refs., 10 figs., 3 tabs.

DOE Contract Number:
AC03-76SF00098
OSTI ID:
484431
Journal Information:
ACM Transactions on Database Systems, Vol. 20, Issue 4; Other Information: PBD: Dec 1995
Country of Publication:
United States
Language:
English