Welcome to the World of Databases!

1
Welcome to the World of Databases!

• Database technology crucial to the operation and
  management of modern organisations
• Major transformation in computing skills
• Significant time commitment
• Exciting journey ahead

2
Subject Goals

• First course in database management
• Practical
• Query formulation for application development
• Data modeling and normalisation
• Background about database administration
• No theoretical proofs or axioms

3
University Database
4
Water Utility Database
5
DBMS Marketplace

• Enterprise DBMS
• Oracle dominates in Unix strong in NT
• SQL Server strong in NT
• Informix significant Unix market share
• DB2 strong in mainframe environment
• Desktop DBMS
• Access dominates
• FoxPro, Paradox, Approach, FileMaker Pro
• Open-source DBMS
• MySQL
• PostgreSQL

6
Tables

• Relational database is a collection of tables
• Heading table name and column names
• Body rows, occurrences of data

Student
7
Entity Integrity primary keys

• Each table has column(s) with unique values
• the primary key
• No two rows with the same primary key value
• No null values in a primary key

8
The Faculty Table
9
What is SQL?

• Structured Query Language
• Language for database definition, manipulation,
  and control
• International standard
• Standalone and embedded usage
• Intergalactic database-speak

10
First SELECT Examples

• See slide 8 for the faculty table
• Example 1
• SELECT
• FROM Faculty
• will list everything in the Faculty table.
• Example 2
• SELECT FacFirstName, FacLastName, FacSalary
• FROM Faculty
• will just list those three columns.

11
First SELECT Examples

• Example 3
• SELECT FacFirstName, FacLastName, FacSalary
• FROM Faculty
• WHERE FacSalary gt 65000
• will just list those with a salary greater
  than 65000.

12
Other Single Table Examples
Example 4 SELECT FacFirstName, FacLastName,
FacSalary FROM Faculty WHERE FacSalary gt
65000 AND FacRank 'PROF Example 5 Testing
for null values SELECT OfferNo, CourseNo FROM
Offering WHERE FacSSN IS NULL NULL is
not the same thing as zero!