《Creatingarelationaldatabase(DDL)FormulatingSQL》.ppt

《Creatingarelationaldatabase(DDL)FormulatingSQL》.ppt

  1. 1、本文档共21页,可阅读全部内容。
  2. 2、有哪些信誉好的足球投注网站(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
  3. 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载
  4. 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
查看更多
《Creatingarelationaldatabase(DDL)FormulatingSQL》.ppt

22 1 1 3 1 5 5 1 1 Introduction * * Relational Database Systems: Creating a relational database (DDL) Formulating SQL queries (DML) Embedded SQL Relational algebra Relational model, relational integrity, etc. Data Modeling: Entity-relationship model Converting an E-R schema into a relational schema Web-Based Database Applications PHP and MySQL Drupal Content Management System (CMS) Course Introduction After this lecture, you should be able to: Understand the differences between Information and Data. Understand the differences between Database and Database Management System (DBMS). Why do we need them? Understand Data Modeling in general, Relational Model in particular. Complete the Assignment 1. Overview of data management From data.gov “Data are values or sets of values representing a specific concept or concepts. Data become information when analyzed and possibly combined with other data in order to extract meaning, and to provide context. The meaning of data can vary according to its context” (Source: Federal Enterprise Architecture Data Reference Model). Data vs. Information Modeling an enterprise, which is an application-world with Entities (e.g., students, courses) Relationships (e.g., Garfield is taking CS275) Creating a database with a database management system (DBMS). Manipulating and Maintaining a database Information Management Data Encoding Information Electronic Charges, Magnetic polarization, etc. Entities, Relationships, etc. Numbers, Strings, Records, Pointers, etc. Bits, Bytes, Pages, etc. Data Modeling A database is an integrated collection of data. A database management system (DBMS) is a software package designed to create and manage a database. The data stored in a database are organized according to the data model supported by the DBMS. A relational database, for example, stores the data in a collection of tables. Database vs. DBMS DBMS Functions Data definition Data manipulation Security and data integrity Recovery and concurrency control

文档评论(0)

jykt + 关注
实名认证
内容提供者

该用户很懒,什么也没介绍

1亿VIP精品文档

相关文档