【文章內(nèi)容簡介】 ide interactive query language is easy to use, such as is responsible for executing the query mand, and query results are displayed on the screen. （ 4） Organize and access data: data storage device on the physical organization and access method in the periphery. （ 5） Transaction management: provide transaction management and operation of the transaction log, security monitoring and data integrity checks, concurrency control and transaction system recovery function. （ 6） The maintenance of the database: provide software support for database administrators, including data security, integrity and security, database backup, database reorganization and performance monitoring and maintenance tools. According to the thus summarizes the technical characteristics of the database, there are 5 characteristics: (1) the data model to represent plex data structures, data redundancy small, easy to expand, to achieve data sharing. (2) data and the independence of procedure has higher, independent database physical and logical independence. (3) the database system provides a convenient user interface for the user. (4) the database system to provide 4 aspects of data control function, respectively is the concurrency control, recovery, integrity and security. The use of the various application data in the database by the database system in accordance with the provisions, establish a certain data model to organize and, by the unified management and centralized control system. (5) increased the flexibility of the system. Select the database management system, the following aspects should be considered: (1) the difficult easy degree structure database. Needs analysis database management system has no paradigm, namely whether the real world must analysis required by the data model of the system, the establishment of the corresponding model。 database management statement is in line with international standards, in line with international standards, the system is easy to maintain, development, transplantation。 is easy to use development tools do not support user oriented。 the database capacity, capacity characteristic database determines the scope of use of the database management system. (2) the degree of difficulty of program development. There is no puter aided software engineering tool CASE puter aided software engineering tools can help developers to provide maintenance, coding environment in the development phase of the method according to software engineering, development, maintenance is convenient for plex software. A design method of the fourth generation language development with a non procedural language platform without the fourth generation language, the user does not need to write code to process plex, and easy to understand, easy maintenance. A logical way of non object oriented design platform the idea of objectoriented design is very similar to humans, to facilitate the development and maintenance. The multimedia data type support multimedia data needs is a development trend in the future, will be a database management system to support multimedia data types to reduce application development and maintenance. (3) performance analysis of database management system. Including evaluating performance (response time, throughput of data per unit time), performance monitoring (internal and external memory usage, system input / output rate, the SQL statement, the database tuples control), performance management (parameter setting and adjustment). (4) for distributed application support. Including data transp