concept of data model transform into relational database theory based on the criteria that means - between。 Then, as the design of information systems, every computer procedures (including procedures for the input and output format), database support services, statements, and inquiries revealed that a detailed examination。 In this so-called Bottom-up analysis, accurate verification of the need to maintain the database and the data in each affairs, statements and so on the needs of those in the nature of the data。

Most of today'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 complete description of the database map。 Logical database design completed, we began to identify in detail the logic of the computer program and maintenance, the report contents of the database for inquiries。

4。Physical database design and definition

Physical database design and definition phase decisions computer memory (usually disk) database in the organization, 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 data-processing database, the physical database design to closely integrate the information systems of other physical aspects of the design, including procedures, computer hardware, operating systems and data communications networks。

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 non-exclusive 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 completion 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 computer 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。

2。2Information 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 life-cycle 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 communications 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 organizations 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 enhance system is mainly to the application of data retrieval application, but not to those who generate and modify database applications。