Research On The Application Of Network Database In The Appraisal System Of Equipment

The task of my thesis originated from "the economic appraisal system of oil field equipment", a large scientific research project cooperated with Liao River Oil Field of Petrol China. On the basis of studying the regulation of life cycle cost a management system of oil filed equipment is build. In this system, the synthetic appraisal method with multi-index performance is adopted. It provides sorts of functions such as equipment information maintenance and economic appraisal through media of internet. As an important part in this system, Database system can make the management of equipment cost data expediently and ensure integrality and security of the data, at the same time implement data-share and so on. It is an absolutely necessarily part of the system. This paper aims at studying the design and implementation of the system's database.Firstly, this paper systematically introduces the development and generation of database technologies as well as the mode of the system development and the related technologies that used in this process. A brief introduction of the equipment economic appraisal system is given as followed. As important points the design and implement of the database maintenance subsystem and the calculation of equipment life cycle cost subsystem are explained. On the base of the knowledge that introduced before, a kind of database system appropriate to the appraisal system is selected. It is the Oracle8i database system.Secondly, this paper discusses the empolder process of this system through discusses the empolder process of database system. The paper focuses on several phases of the empolder process, such as requirement-analysis, concept-structure-design, logic-structure-design. The constraint to data integrity and the data discount as well as data module building are given high light on their implement by trigger and procedure.Thirdly, this paper discusses the security and optimization of database system. On one hand, the paper discusses the security-measure, backup scheme and its method through discusses database-security. On the other hand, the paper discusses the optimization-method of this system through discussing the definition and its method of database-optimization.Base on the design as introduced before, the subsystems of life cycle cost and database maintenance are implemented.