第11章-计算机专业英语-孙建忠PPT优秀课件

11.1 Overview
Chapter 11 Database Management
❖ Database(sometimes spelled data base) is also called an electronic database, rerferring to any collections of data, or information, that is specially organized for rapid search and retrieval by a computer. Database are structured to facilitate the storage, retrieval, modification, and deletion of data in conjunction with various dataprocessing operations. Database can be stored on magnetic disk or tape, optical disk, or some other secondary storage device.
❖ 数据库（有时拼成 data base）也称为电子数据库，是指由计算机 特别组织的用于快速查找和检索的任意的数据或信息集合。数据库 与其他数据处理操作协同工作，其结构要有助于数据的存储、检索、 修改和删除。数据库可存储在磁盘或磁带、光盘或某些辅助存储设 备上。
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Chapter 11 Database Management
Classification of the logical structuring techniques of DBMS
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Chapter 11 Database Management
11.1 Overview
New Words & Expressions:
facilitate 使容易，促进 field n. 字段， alphabetically 按字母顺序地 break down v. 分解 encyclopedia n. 百科全书 biblБайду номын сангаасography 书目，参考书目 literature n. 文献，著作
retrieval n. 检索 record 记录， chronologically 按年代顺序排 build up 建造，装配，组成 reference n. 涉及，参考，引用 periodical n. 期刊，杂志 professional n. 专业人员，专家
Abbreviations:
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Chapter 11 Database Management
11.1 Overview
Database records and files must be organized to allow retrieval of the information. Early systems were arranged sequentially (i.e., alphabetically, numerically, or chronologically); the development of direct-access storage devices made possible random access to data via indexes. Queries are the main way users retrieve database information. Typically, the user provides a string of characters, and the computer searches the database for a corresponding sequence and provides the source materials in which those characters appear. A user can request, for example, all records in which the content of the field for a person’s last name is the word Smith.
Computer English
Chapter 11 Database Management
Chapter 11 Database Management
Key points: useful terms and definitions
of Database Management Difficult points:
11.1 Overview
A database consists of a file or a set of files. The information in these files may be broken down into records, each of which consists of one or more fields. Fields are the basic units of data storage, and each field typically contains information pertaining to one aspect or attribute of the entity described by the database. Using keywords and various sorting commands, users can rapidly search, rearrange, group, and select the fields in many records to retrieve or create reports on particular aggregates of data. 一个数据库由一个文件或文件集合组成。这些文件中的信息可分解成一个 个记录，每个记录有一个或多个域。域是数据存储的基本单位，每个域一 般含有由数据库描述的属于实体的一个方面或一个特性的信息。用户使用 关键词和各种排序命令，能够快速查找、重排、分组并在查找的许多记录 中选择相应的域，建立特定集上的报表。