Generating an optimized set of relational queries fetching data in an object-relational database

摘要

The processing of object-oriented queries so as to retrieve data from a relational database management system (RDBMS) is described. An object- oriented query and at least one prefetch path are received from an object- oriented source (such as an application or user). The prefetch path identifies one or more objects which are desired to be constructed. The object-oriented query is translated to a translated object query, where the translated object query is a relational database query capable of retrieving from the RDBMS data to initialize base attributes of top- level objects identified by the object-oriented query. A set of relational queries is generated from the translated object query and the prefetch path. These relational queries, which are capable of retrieving from the RDBMS data needed to construct the objects identified by the prefetch path, are processed by the RDBMS.