THE DATABASE ENVIRONMENT Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information. ~ T.S. Eliot ~

Learning Objectives  Concretize the concepts of data, information, data management and metadata  Explain what a database is and why databases are important  Describe a database management system  Differentiate between the DBMS and a database  Describe the different data models and abstraction layers  Explain the similarities and differences among DBMS products  Explain DBMS history and modern uses  Describe how data is physically stored in primary and secondary storage

Before we begin…What’s… Data? Information? Data Management? Metadata? Query?

Data or Information?

Where’s the Data? Where’s the Metadata?

Where is the: Data? Meta- Data?

Activity: Data or Meta-Data? 1. A Zip Code: A Zip Code is 5 Characters XXXXX 3. A List of First Names: Tom, Dick, Harry 4. A Picture, Like This One: 5. The Name of the Picture file FrostTrees.jpg 6. When you place an order, the quantity of the item ordered must be a number >0

Something strange and confusing :  Data can be information:  $5 (the amount of money in my wallet)  Information can be data:  I calculate student final grades, then place them on a form sent to the registrar’s office.  Metadata can be data:  The names of MP3 files in your personal collection. Actually it’s all about context!

What is it, part duex! Database Database Management System (DBMS)

Elements of a Database Meta-Data Data Database Data-Management Data “In” Information “Out” End-User DBMS is software. It stores the data/meta data and “enables” data-management

Clarification via Family Guy  Brian can write his novel on a typewriter or w/pen and paper.  But there are obvious advantages to using word processing software.  Most databases use DBMS’s just like most papers are written with word processors Database  Brian’s Novel DBMS  WP Software Database  Brian’s Novel DBMS  WP Software

Database or DBMS?

Data or Metadata? Database? DBMS?

Data or Metadata? Database? DBMS?

Evolution of DBMSs

Enterprise DBMS Market Share ProductShare Oracle44.4% IBM (DB2)21.2% Microsoft (SQL Server)18.6% Others: (Sybase, NCR Terdata, etc…)5.9% Open Source (MySQL, PostgreSQL, etc…)9.9% * Source: Computerworld 2007

DBMS deployment plans 2008 * source: gartner

An employable skill in the future. Source BLS:

Data Models: Abstraction Levels Conceptual Internal External Physical Logical Highly Abstract Hardware and Software Independent Somewhat Abstract Hardware Independent Software Dependent Not Abstract (Concrete) Hardware and Software Dependent

Elements of the DBMS Approach  Enterprise Data Model  Graphical model showing high-level entities and relationships for the organization  Relational Databases  Database technology involving tables (relations) representing entities and primary/foreign keys representing relationships  Use of Internet Technology  Networks and telecommunications, distributed databases, client-server and 3-tier architectures  Database Applications  Application programs used to perform database activities CRUD for database users

THE DATABASE ENVIRONMENT Questions?