The use of hints in Object-Relational query optimization
Object-Relational queries are queries which can handle data objects feature on the existing relational data environment. REF is one of most important data structures in Object-Relational Databases can be explained as a logical pointer to define the link between two tables which similar function to pointers in object oriented programming language. There are three ways of writing REF join queries which are: REF Join, Path Expression join and DEREF/VALUE join. In this paper, we study optimization technique for Object-Relational queries using hints. Hints are additional comments which ate inserted into in SQL statement for the purpose of instructing or suggesting the optimizer to perform the specified operations. We utilize various hints including Optimizer hints, Table join and anti-join hints, and Access method hints. We analyse performance of various object-relational queries particularly in three ways of writing REF queries using the TRACE and TKPROF utilities which provide query execution statistics and execution plans.
object-relational query optimization ref orbms