Querying Objects with Complex Static Structure
نویسندگان
چکیده
This paper describes the database algebra QAL which serves as the logical algebra in the query execution system of the Distributed Object Kernel [25]. QAL is based on the concepts of the early functional query languages. It provides a simple functional semantics of the language and the means to express complex queries in a step-by-step manner. The operations of QAL are designed to allow simple and e cient manipulation of objects having rich classi cation structure, complex hierarchical or network structure. The expressive power of QAL is presented through a case-study consisting of a comprehensive set of examples of queries which manipulate complex objects.
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تاریخ انتشار 1998