400 likes | 462 Views
Objectives Overview. See Page 351 for Detailed Objectives. Objectives Overview. See Page 351 for Detailed Objectives. Databases, Data, and Information. Page 352. Databases, Data, and Information. Pages 352 – 353 Figure 9-1. Databases, Data, and Information.
E N D
Objectives Overview See Page 351 for Detailed Objectives Discovering Computers Fundamentals, 2010 Edition Chapter 9
Objectives Overview See Page 351 for Detailed Objectives Discovering Computers Fundamentals, 2010 Edition Chapter 9
Databases, Data, and Information Page 352 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Databases, Data, and Information Pages 352 – 353 Figure 9-1 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Databases, Data, and Information • Database software,often called a database management system(DBMS), allows users to: Page 352 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Databases, Data, and Information • Data integrity identifies the quality of the data • Garbage in, garbage out (GIGO) points out the accuracy of a computer’s output depends on the accuracy of the input Page 353 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Databases, Data, and Information • Valuable information should have the following characteristics: Page 354 Discovering Computers Fundamentals, 2010 Edition Chapter 9
The Hierarchy of Data • Data is organized in layers • Files, records, fields, characters Page 355 Figure 9-2 Discovering Computers Fundamentals, 2010 Edition Chapter 9
The Hierarchy of Data • A character is one byte • Numbers, letters, space, punctuation marks, or other symbols • A field is a combination of one or more related characters • Field name • Field size • Data type Pages 355 – 356 Figure 9-3 Discovering Computers Fundamentals, 2010 Edition Chapter 9
The Hierarchy of Data • Common data types include: Page 356 Discovering Computers Fundamentals, 2010 Edition Chapter 9
The Hierarchy of Data • A record is a group of related fields • A primary keyuniquely identifies each record • A data fileis a collection of related records Page 356 Figure 9-4 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Maintaining Data • File maintenancerefers to the procedures that keep data current Pages 357 - 358 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Maintaining Data • Users add new records to a file when they obtain new data Page 357 Figure 9-5 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Maintaining Data • Users modify a record to correct inaccurate data or update old data Pages 357 - 358 Figure 9-6 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Maintaining Data • When a record no longer is needed, a user deletes it from a file Pages 358 - 359 Figure 10-7 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Maintaining Data • Validation compares data with a set of rules or values to find out if the data is correct Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click Data Validationbelow Chapter 9 Pages 359 - 360 Discovering Computers Fundamentals, 2010 Edition Chapter 9
File Processing Versus Databases Pages 361 - 362 Discovering Computers Fundamentals, 2010 Edition Chapter 9
File Processing Versus Databases Page 362 Figure 9-10 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click MySQLbelow Chapter 9 Page 363 Figure 9-11 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems • A data dictionarycontains data about each file in the database and each field in those files Page 364 Figure 9-12 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems • A DBMS provides several tools that allow users and programs to retrieve and maintain data in the database Pages 364 - 366 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems • A query languageconsists of simple, English-like statements that allow users to specify the data to display, print, or store • Query by example(QBE) provides a GUI to assist users with retrieving data Pages 364 - 366 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems Page 365 Figure 9-13 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems • A form is a window on the screen that provides areas for entering or modifying data in a database Page 366 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems • A report generatorallows users to design a report on the screen, retrieve data into the report design, and then display or print the report Page 366 Figure 9-15 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click Data Securitybelow Chapter 9 Page 367 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Management Systems • A DMBS provides a variety of techniques to restore the database to a usable form in case it is damaged or destroyed Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click Continuous Backup below Chapter 9 Page 367 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Relational, Object-Oriented, and Multidimensional Databases • A data modelconsists of rules and standards that define how the database organizes data • A relational databasestores data in tables that consist of rows and columns • Each row has a primary key • Each column has a unique name • A relationship is a link within the data Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click Relational Databases below Chapter 9 Page 368 Figure 9-17 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Relational, Object-Oriented, and Multidimensional Databases • Structured Query Language(SQL) is a query language that allows users to manage, update, and retrieve data Page 369 Figure 9-18 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Relational, Object-Oriented, and Multidimensional Databases • An object-oriented database (OODB) stores data in objects • Object-oriented databases often use Object Query Language (OQL) to manipulate and retrieve data Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click Object-Oriented Databases below Chapter 9 Page 369 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Relational, Object-Oriented, and Multidimensional Databases • A multidimensional databasecan store data in more than two dimensions of data • Sometimes known as a hypercube • Can consolidate data much faster than a relational database • A data warehouse is a huge database that stores and manages the data required to analyze historical and current transactions Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click Data Warehousesbelow Chapter 9 Page 370 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Web Databases • Databases on the Web allow you to: Pages 370 - 371 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Web Databases Page 371 Figure 9-19 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Video: How a Photo Sharing Site Keeps Its Data CLICK TO START Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Administration • It is important to have a carefully designed database Click to view Web Link,click Chapter 9, Click Web Link from left navigation, then click Database Design Guidelines below Chapter 9 Page 371 Figure 9-20 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Administration Page 371 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Database Administration • Employees should learn how to use the data in the database effectively • Interact with database • Identify new data for the database • Maintain the database Page 372 Discovering Computers Fundamentals, 2010 Edition Chapter 9
Summary Page 372 Discovering Computers Fundamentals, 2010 Edition Chapter 9