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

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 theData?Where’s the Metadata?

Where is the:

Data?Meta-Data?

Activity: Data or Meta-Data?

1. A Zip Code: 132442. A Zip Code is 5 Characters XXXXX3. A List of First Names: Tom, Dick, Harry4. A Picture, Like This One:5. The Name of the Picture

file FrostTrees.jpg6. 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

DatabaseData-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 NovelDBMS WP Software

Database or DBMS?

Database or DBMS?

Database or DBMS?

Database or DBMS?

Database or DBMS?

Database or DBMS?

Database or DBMS?

Data or Metadata?

Database?

DBMS?

Data or Metadata?

Database?

DBMS?

Evolution of DBMSs

Enterprise DBMS Market Share

Product Share

Oracle 44.4%

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: 2008http://www.bls.gov/oes/current/oes151061.htm

Data Models: Abstraction Levels

Conceptual

Internal

External

Physical

Logical

Highly AbstractHardware and Software

Independent

Somewhat Abstract Hardware IndependentSoftware 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?