Database Fundamentals
COMS2002
Lecturer: Dr. Hima Vadapalli
Semester I, 2019
Why do I need a database
course?
Learning Outcomes
• Know fundamental design concepts
• Evolution of database systems, relational database
systems
• Construct and interpret database blueprint
• Comprehend and apply business rules in developing a
database design
• Construct query statements
Teaching Schedule
— Lecture : Tuesdays (08h00 – 09h45)
— Tutorials: Alternate Thursdays (12h30 – 13h15)
— Labs : Alternate Wednesdays (10h00 – 12h00)
Refer to cle.wits.ac.za for complete calendar
Assessments
— Class Mark - 50%
— Class test - 20%
— Labs - 10%
— Assignment - 20%
— Exam Mark - 50%
— Lab exam - 20%
— Written exam - 30%
— Final mark - Class mark + Exam mark
PRESCRIBED TEXTBOOK
Code of Conduct
Questions?
Database Systems
Objectives
— The differences between data and information
— What is a database and various types of databases
— The importance of database design
— How modern databases evolved from file systems
— What are the database system’s main components
— How a database system differs from a file system
— The main functions of a database management system
(DBMS)
Data vs. Information
— Data are raw facts
— Information is the result of processing raw data to
reveal meaning
— Information requires context to reveal meaning
— Raw data must be formatted for storage, processing,
and presentation
— Data are the foundation of information, which is the
bedrock of knowledge
Database and the DBMS
— Database: shared, integrated computer structure that
stores a collection of data
— End-user data: raw facts of interest to the end user
— Metadata: data about data
— Metadata provides description of data characteristics
and relationships in data
— Complements and expands value of data
— Database management system (DBMS): collection of
programs
— Manage structure and control access to data
Role of the DBMS
— DBMS is the intermediary between the user and the
database
Thus
— DBMS enables data to be shared
— DBMS integrates many users’ views of the data
Advantages of the DBMS
— Advantages of a DBMS:
— Improved data sharing
— Improved data security
— Better data integration
— Minimized data inconsistency
— Improved data access
— Improved decision making
— Increased end-user productivity
Functions of the DBMS
— Stores data and meta data
— Creates complex structures for data storage
— Transforms data to conform to data structures
— Creates a security system
— Creates complex structures for multi user access
— Performs backup and recovery
— Provides access to data via utility programs and
programming language interfaces
— Better data integration
— Minimized data inconsistency