【正文】 s database, these rules from the relational database theory and the process known as standardization. This step is the result of management of these data have not cited any database management system for a plete description of the database map. Logical database design pleted, we began to identify in detail the logic of the puter program and maintenance, the report contents of the database for inquiries. 4. Physical database design and definition Physical database design and definition phase decisions puter memory (usually disk) database in the anization, definition of According to the library management system for physical structure, the procedures outlined processing services, produce the desired management information and decision support statements. The objective of this stage is to design an effective and safe management of all dataprocessing database, the physical database design to closely integrate the information systems of other physical aspects of the design, including procedures, puter hardware, operating systems and data munications works. 5. Database Implementation The database prepared by the realization stage, testing and installation procedures for handling databases. Designers can use the standard programming language (such as COBOL, C or Visual Basic), the dedicated database processing languages (such as SQL), or the process of the nonexclusive language programming in order to produce a statement of the fixed format, the result will be displayed, and may also include charts. In achieving stage, but also the pletion of all the database files, training users for information systems (database) user setup program. The final step is to use existing sources of information (documents legacy applications and databases and now needs new data) loading data. Loading data is often the first step in data from existing files and databases to an intermediate format (such as binary or text files) and then to turn intermediate loading data to a new database. Finally, running databases and related applications for the actual user maintenance and retrieval of data. In operation, the regular backup database and the database when damaged or affected resume database. 6. Database maintenance During the database in the progressive development of database maintenance. In this step, in order to meet changing business conditions, in order to correct the erroneous database design, database applications or processing speed increase, delete or change the structure of the database. When a procedure or failure of the puter database affect or damage the database may also be reconstruction. This step usually is the longest in the database development process step, as it continued to databases and related applications throughout the life cycle, the development of each database can be seen as a brief database development process and data modeling concepts arise, logical and physical database design and database to achieve dealing with the changes. Information System developed by other means System Development Life Cycle minor changes in law or its variant of the often used to guide information systems and database development. Information System is a lifecycle methodology, it is highly structured approach, which includes many checks and balances to ensure that every step of produce accurate results, and new or alternative information system and it must munications or data definitions consistent existing system needs consistency. System development life cycle because of the regular need to have a working system for a long time been criticized because only work in the system until the end of the whole process generated. More and more anizations now use rapid application development method, it is a includes analysis, design and implementation of steps to repeat the rapid iterative process until convergence to users the system so far. Rapid Application Development Act required the database has been in existence, and 。s information system blueprint. In the information system planning, you can build an enterprise data model as a whole information system architecture part. According to Zachman (1987), Sowa and Zachman (1992) views of an information system architecture consists of the following six key ponents: Data (Figure 1 shows, but there are other methods that). Manipulation of data processing (of a data flow diagram can be used, with the object model methods, or other symbols that). Networks, which anizations and in anizations with its main transmission of data between business partners (it can connect through the work topology map and to demonstrate). People who deal with the implementation of data and information and is the source and receiver (in the process model for the data shows that the sender and the receiver). Implementation of the events and time points (they can use state transition diagram and other means.) The reasons for the incident and data processing rules (often in the form of text display, but there are also a number of charts for the planning tools such as decision tables). Information Engineering Information systems planners in accordance with the specific information system planning methods developed information system architecture. Information engineering is a popular and formal methods. Information engineering is a dataoriented creation and maintenance of the information system. Information engineering is because the dataoriented, so when you begin to understand how the database is defined by the logo and when information engineering a concise explanation is very helpful. Information Engineering follow topdown planning approach, in which specific information systems from a wide range of information needs in the understanding derived from (for example, we need about customers, products, suppliers, sales