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SQL: A Query Language for Manipulation Object-oriented Databases



Stanley Su, A Alashqur, H Lam


An essential property which is desirable in a query language designed for a certain data model is that queries issued in that language must produce results that are structured and modeled using the same data model. A consequence of maintaining this property in a query language is that the result of a query can be used as an operand in some other query (or queries) or can be saved as a user''s view. Existing query languages that have been designed for the class of object-oriented data models do not posses this property. In this paper, we introduce the object-oriented query language (OQL), which maintains this property. An OQL query is considered as a function, which when applied to a database, returns a subdatabase whose structure consists of some selected object classes and their associations. The objects that satisfy the search conditions and participate in the patterns of object associations specified in the query constitute the extension of the resulting subdatabase. A subdatabase forms a context under which system-defined an/or user-defined operations can be specified and performed. Several advanced features such as branching association patterns and set operations on subdatabases are also presented.
Proceedings Title
Proceedings of the 15th International Conference on Very Large Data Bases
Conference Location


Su, S. , Alashqur, A. and Lam, H. (1989), SQL: A Query Language for Manipulation Object-oriented Databases, Proceedings of the 15th International Conference on Very Large Data Bases, , USA (Accessed April 23, 2024)
Created December 31, 1988, Updated October 12, 2021