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Chapter 11 . Databases. Overview. Describe How Data is Organized Define Key Fields Compare Batch and Real-time Processing Define Five Common Database Models Distinguish the Kinds Of Databases Discuss Strategic Uses and Security Concerns. Data Organization . Field
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Chapter 11 Databases
Overview • Describe How Data is Organized • Define Key Fields • Compare Batch and Real-time Processing • Define Five Common Database Models • Distinguish the Kinds Of Databases • Discuss Strategic Uses and Security Concerns
Data Organization • Field • Combination of Related Characters • Characteristics • Name Uniquely Identifies Each Field • Data Type • Size • Record • Group of Related Fields • Key Field • AKA Primary Key • Uniquely Identifies Each Record
Data Organization • Table • Collection of Related Records • Each Record Contains Same Fields • Each Field Contains Different Data • Database • Group of Related Tables
Batch and Real-time Processing • Batch Processing • Data Collected Over Several Hours, Days, or Weeks • Processed All at Once as a “Batch” • Real-time Processing • AKA Online Processing • Data Processed at Same Time Transaction Occurs
Databases • Need • Sharing • Information Readily Shared Between Departments • Security • Users Access Only the Kind of Information They Need • Less Data Redundancy • Redundancy Causes • Inefficient Use of Storage Space • Data Maintenance Problems • Data Integrity • Multiple Sources of Data Lead to Variations
Databases • Validation • Comparing Data with Set of Rules • Reduce Data Entry Errors • Enhance Data Integrity • Types • Alpha / Numeric • Range • Completeness • Consistency
Database Management • Database Management System (DBMS) • Subsystems • DBMS Engine • Bridges Logical View and Physical Views of Data • Data Definition • Data Dictionary
Database Management • Database Management System (DBMS) • Subsystems • Data Manipulation • Query-by-example, SQL • Application Generation • Data Entry Forms • Data Administration • Maintaining Security • Processing Rights
DBMS Structure • Models • Hierarchical • One-to-many Relationship • Rigid Structure • Network • Many-to-many Relationship • Flexible and Efficient
DBMS Structure • Models • Relational • No Hierarchical Access Paths • Data Elements Stored in Different Tables • Consist of Rows (Records) & Columns (Fields) • Each Row Has Primary Key • Related Tables Must Have Common Field
DBMS Structure • Models • Multidimensional • Data Viewed as a Cube Having Three or More Sides • Represent Complex Relationships Between Data • Click Stream • Object-oriented • Stores Data in Objects • Can Contain Both Data and Actions
Types of Databases • Individual • Primarily Used by Just One Person • Company • Stored on a Central Database Network Server • Distributed • Not All Data Physically Located in One Place • Accessible Through a Variety of Networks • Commercial • Large Database that Covers a Specific Subject • Access Offered to the Public for a Fee
Database Uses and Issues • Strategic Uses • Data Warehouse • Data Mining • Business Directories • Demographics • Business Statistical • Text • Web
Careers in IT • Database Administrator • Determine Ways to Organize and Access Data • Maintain Database Security • Back Up System • Bachelor's Degree in Computer Science • Technical Experience • Annual Salary of $67,000 - $98,000