A PROCEDURAL SEMANTICS FOR STRATIFIED DATABASE UPDATES

This paper investigates efficient evaluation of database updates and p resents a procedural semantics for stratified update programs that ext end stratified logic programs with bulk updates and hypothetical reaso ning. Bulk rules with universal quantification in the body allow an ar bitrary update to be applied simultaneously for every answer of an arb itrary query. Hypothetical reasoning is supported by testing the succe ss or failure of an update. The procedural semantics offers efficient goal-oriented tabled evaluation of database updates. It guarantees ter mination for function-free stratified update programs and avoids repea ted computation of identical subgoals.