H. Lewis Chau

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Although the concept of roles is becoming a popular research issue in object-oriented databases and has been proven to be useful for dynamic and evolving applications , it has only been described conceptually in most of the previous work. Moreover, the important issues such as the semantics of roles (e.g., message passing) are seldom discussed. Furthermore,(More)
In many class-based object-oriented database systems the association between an instance and a class is both exclusive and permanent. Therefore, these systems have serious diiculties in representing objects taking on diierent and multiple roles over time. In this paper, a novel object-oriented database management system, called DOOR, which supports object(More)
The association between an instance and a class is exclusive and permanent i n many class-based, object-oriented database systems. Therefore, these systems have serious dificulties f o r applications in which objects takes on different and multiple roles over time. Recently, some researchers have proposed the use of roles to tackle these problems. Although(More)