The Power of Methods With Parallel Semantics

A model capturing the data manipulation capabilities of a large class of methods in ohjectoriented databases is proposed and investsigated. The model uses a deterministic, parallel synchronous semantics with concurrentread and concurrent-write. The results focus on the expressive power of methods and help understand various constructs and semantics associated with methods. Restrictions of methods providing va.rious tract,ability guarantees are also discussed. The restrictions correspond closely to well-known relational query languages such aa relational calculus, Datalog, the fixpoint queries, and the while queries. They provide complexity bounds such as constant parallel time, PTIMF, and PSPACE. Exact characterizations for some complexity classes are also obGncd under certain assumptions. Our methods provide a model of database parallel computation which makes explicit the potential parallelism in databases. We compare our model to traditional parallel computation models such as PRAM...

• Type: Conference
• Year: 1991
• Where: VLDB
• Authors: Karl Denninghoff, Victor Vianu
• Keywords: Database, Model, Parallel Computation, Parallel Synchronous Semantics, VLDB 1991