tailieunhanh - FUNDAMENTALS OF DATABASE SYSTEMS Fourth Edition phần 5

số dự án của một trong các dự án mà nhân viên các công trình trên (PNUMBER), và số giờ mỗi tuần người lao động làm việc trên đó dự án (GIỜ). Tuy nhiên, cả hai lược đồ có một giải thích rõ ràng và rõ ràng. Lược đồ DEPT _LOCATIONS đại diện cho một thuộc tính multivalued | 400 Chapter 12 Practical Database Design Methodology and Use of UML Diagrams FIGURE The design of the university database as a class diagram. What we have described above is a partial description of the capabilities of the tool as it related to the conceptual and logical design phases in Figure . The entire range of UML diagrams we described in Section can be developed and maintained in Rose. For further details the reader is referred to the product literature. Appendix B develops a full case study with the help of UML diagrams and shows the progression of design through different phases. Figure gives a version of the class diagram in Figure drawn using Rational Rose. Automated Database Design Tools I 401 If Sp. ttfication for OH I MPIIJYI t _ JX Relation I Components I Ne ỉed I Patent PAhr Documentation j ũM_EMFtŨỶẼẼl Hame. Iwe class Stereotype I Export Control FIGURE The class OM_EMPLOYEE corresponding to the table Employee in Figure . Automated Database Design Tools The database design activity predominantly spans Phase 2 conceptual design Phase 4 data model mapping or logical design and Phase 5 physical database design in the design process that we discussed in Section . Discussion of Phase 5 is deferred to Chapter 16 in the context of query optimization. We discussed Phases 2 and 4 in detail with the use of the UML notation in Section and pointed out the features of the tool Rational Rose which support these phases. As we pointed out before Rational Rose is more than just a database design tool. It is a software development tool and does database modeling and schema design in the form of class diagrams as part of its overall object-oriented application development methodology. In this section we summarize the features and shortcomings of the set of commercial tools that are focussed on automating the process of conceptual logical and physical design of databases. When database technology was