1数据库管理系统的介绍.doc

数据库管理系统的介绍
Raghu Ramakrishnan[ Database Management Systems( 3th Edition ),Wiley ,2004, 5-12
]
　　　数据库（database,有时拼作data base）又称为电子数据库，是专门组织起来的一组数据或信息，其目的是为了便于计算机快速查询及检索。数据库的结构是专门设计的，在各种数据处理操作命令的支持下，可以简化数据的存储，检索，修改和删除。数据库可以存储在磁盘，磁带，光盘或其他辅助存储设备上。
Database Management Systems( 3th Edition ),Wiley ,2004, 5-12
　　　A introduction to Database Management System
　　　Raghu Ramakrishnan
　　　A database (sometimes spelled data base) is also called an electronic database , referring to any collection of data, or information, that is specially organized for rapid search and retrieva l by a computer. Databases are structured to facilitate the storage, retrieva l , modification, and deletion of data in conjunction with various data-processing operations .Databases can be stored on magnetic disk or tape, optical disk, or some other secondary storage device.