0 / Database Management

1 / Identify file maintenance techniques Discuss the terms character, field, record, and table Describe characteristics of relational and object-oriented databases Explain how to use a query language Understand how Web databases work Discuss the functions most common to DBMSs Identify the qualities of valuable information Understand the concept of a data warehouse

2 / Database  AKA Database Management System (DBMS)  Collection of Data  Organized for Quick Access, Retrieval, & Use  Databases Allow You to  Create Database  Add, Change, & Delete Data  Sort & Query Database  Print Reports

3 / Data Integrity  Degree to Which Data is Correct  When Database Contains Errors, it Loses Integrity  GIGO (Garbage In, Garbage Out)  Cannot Create Correct Information From Incorrect Data

4 / Qualities of Valuable Information  Accurate  Verifiable  Timely  Organized  Accessible  Useful  Cost-effective

5 / Data Hierarchy  Database Contains Files  File Contains Records  Record Contains Fields  Field Contains Characters

6 / Field  Combination of One or More Characters  Smallest Unit of Data User Accesses

7 / Field Characteristics  Field Name Uniquely Identifies Each Field  Data Type  Text  Numeric  Autonumber  Currency  Date  Memo  Hyperlink  Object  Field Size

8 / Record  Group of Related Fields  Key Field  AKA Primary Key  Uniquely Identifies Each Record

9 / Table / File  Collection of Related Records Stored on Disk  Each Record in File Contains Same Fields  Each Field Contains Different Data  Database Composed of Group of Related Tables / Files

10 / Popular DBMS PC, midrange server, mainframeIBM CorporationDB2 PC, midrange server, mainframeIBM CorporationInformix ServerMicrosoft CorporationSQL Server PC, midrange server, PDASybase Inc.Sybase PC, midrange server, mainframe, PDAOracle CorporationOracle PC, midrange server, mainframeComputer Associates International, Inc. Ingres PC, server, PDAMicrosoft CorporationAccess Computer TypeManufacturerDatabase

11 / File Maintenance  Procedure That Keeps Data Current  Add Records  When You Obtain New Data  Change Records  Correct Inaccurate Data  Update Existing Data  Delete Records  Record No Longer Needed

12 / Validation  Process of Comparing Data with a Set of Rules  Find Out if Data is Correct  Reduce Data Entry Errors  Enhance Data Integrity

13 / Validation  Types  Alpha / Numeric  Correct Data Type Entered  Range  Number is in Specified Range  Completeness  Required Field Contains Data  Consistency  Check Digit

14 / Data Dictionary  Contains Data About Each File in Database  Contains Data About Each Field in Those Files

15 / Form  On Screen Window  Provides Areas for Entering / Changing Data in a Single Record

16 / Report Generator  Generates Report Without User’s Knowledge of Programming

17 / Report Types  Detailed  Summary  Consolidates Data  Exception  Identifies Data Outside of Norm  Conditions Define Status Range

18 / Query  Request Specific Data from Database  SQL (Structured Query Language)  Allow Users to Specify Data to Display, Print, or Store  QBE (Query By Example)  Retrieves Records that Match Criteria Entered in Form Fields QBECriteria Result

19 / File Processing System  Each Department Has Own Set of Files  Records in One File May Not Relate to Records in Other Files  Weakness  Redundancy  Same Fields Stored in Multiple Files  Isolated  Difficult to Access

20 / Database System  Many Programs & Users Can Share Data  Secures Data  Only Authorized Users Can Access Certain Data  Can View Data But Not Update or Change It

21 / Storage Differences

22 / Database System Strengths  Reduced Redundancy  Improved Integrity  Shared Data  Easier Access  Reduced Development Time

23 / Data Model  How Database Organizes Data  Defines How Users View Data  Types  Relational  Object-oriented  Multidimensional

24 / Relational Database  Stores Data in Tables  Consist of Rows & Columns  Each Row has Primary Key  Related Tables Must Have a Common Field table column relationships row

25 / Object-oriented Database (OODB)  Stores Data in Objects  Can Contain Both Data & Activities That Read / Process Data  Advantages  Can Store More Types of Data  Can Access Data Faster  Example  Multimedia Database  Store Images, Audio, and/or Video

26 / Multidimensional Database  Stores Data in Dimensions  Multiple Dimensions Allow Users to Analyze Any View of Data  AKA Hypercube  Advantages  Consolidates Data Much Faster than Relational Database

27 / Multidimensional Database  Data Warehouse  From Multiple Databases  Comprehensive Data  Required to Analyze Data Across Enterprise  Examples  Data Mining  Process of Finding Patterns & Relationships Among Data  Click Stream  Collection of Every Action Users Makes in Web Site

28 / Database Development Guidelines