QAL: A Query Algebra of Complex Objects
نویسندگان
چکیده
The main motivation for the development of a query algebra of complex objects QAL is the study of the operations needed to query the structural aspects of object-oriented databases which are due to the advantages of the object-oriented database model over conventional relational and functional database models. The basic operations of the QAL query algebra evolved from relational algebras and the FQL family of functional query languages by re ning their operations for the manipulation of objects. In order to support the features speci c to object-oriented data models, QAL o ers: (i) a set of operations which provide the means for querying conceptual schemata, and (ii) an operation which provides a simple and e cient way of querying nested components of complex objects. We show through a case-study consisting of a comprehensive set of examples how these operations can be employed to express a class of queries speci c to object-oriented databases.
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عنوان ژورنال:
- Data Knowl. Eng.
دوره 30 شماره
صفحات -
تاریخ انتشار 1999