1. Introduction to Databases
By Faraz Ahmed

2. Recommended Text/ Reference Books
Fundamentals of Database Systems,
3rd Edition by Elmasri & Navathe
Database System Concepts
3rd Edition by Abraham Silbershatz, Henery F. Korth, Sudarshan
An introduction to Database Systems
By C.J. Date
Faraz Ahmed

3. Programming Skills Front-End Development Back-End Development
ASP.NET using C#/VB.Net, C++, PHP
Back-End Development
MS-Access, Oracle 9i or higher, MS SQL Server
Documentation
ER-Win, Visio, MS-Word
Faraz Ahmed

4. Top Database Groups
Academia:
1) Stanford University, 2) University of Wisconsin, Madison, 3) University of California, Berkeley, 4) University of Maryland, College Park, 5) University of Washington.
Research Labs:
1) IBM Almaden Research Lab, 2) AT&T Research Labs, 3) Microsoft Research Lab, 4) Lucent Technologies.
Database Products:
1) Oracle, 2) IBM DB2, 3) MySQL, 4) Sybase, 5) MS SQL Server, 6) Informix.
Faraz Ahmed

5. Types of Databases Flat Files Hierarchical Relational
Object Relational
Object Oriented
Web Enabled (Online DBs)
Faraz Ahmed

6. Overview Data: Known facts that can be recorded
Database: Collection of Integrated data
Typically models a real-world “enterprise”
DBMS: A software system designed to store, manage, and facilitate access to databases.
Faraz Ahmed

7. Data vs. Information Data: Raw facts/Un-processed information
But they are building blocks for information
Information: Data Processed to reveal its meaning
Information is meaningful
In today’s world, accurate, relevant and timely information is the key to good decision making
Good decision making is key to survival in today’s competitive and global environment
Faraz Ahmed

8. Data and Information …
Data: is known recorded facts which has specific meanings or interpretation.
Example: the numbers 10.5, 22, and 119 are data
Information: is a precise, understandable and specific representation of data.
Example: The temperature of room 119 in building 22 is 10.5, is an information
Knowledge: is something which is derived or inferred from available information using some level of intelligence.
Example: Based on experience, the above information can be used to infer that the room is quite cold and could cause some inconvenience if we work on that room for a long period of time with out wearing worm clothes.
Faraz Ahmed

9. The Need
Faraz Ahmed

10. Files and Databases
Files: A collection of records or documents dealing with one organization, person, area, or subject. It could either be:
Computer files
Manual files (Paper)
Database: A collection of similar records with relationships between records.
Statistical, Business Data
Faraz Ahmed

11. Database vs. File Systems

12. Database
A database is collection of stored operational data used by application systems of some particular enterprise (C.J. Date)
Paper Database
Still contain a large portion of world's knowledge
File Processing Systems
Early batch processing of business data
Database Management Systems (DBMS)
Will cover in detail
Faraz Ahmed

13. File Processing Systems
Collection of application programs that performs services for the end-users (e.g. Reports)
Each program defines and maintains its own data
Faraz Ahmed

14. File Processing Systems
Faraz Ahmed

15. File Processing Systems
Faraz Ahmed

16. -- File-Based Approach
User 1
Application programs
Data
Data
Application programs
User 2
Faraz Ahmed

17. Limitations of File-based Approach
Separation and isolation of data
Each program maintains its own set of data. Users of one program may be unaware of potentially useful data held by other programs.
Duplication of data
Same data is held by different programs. Wasted space and potentially different values and/or different formats for the same item.
Atomicity of updates
Failure may lead database to an inconsistent state with partial updates carried out
E.g. Transfer of funds from one account to another should either be complete or incomplete, no in-between state
Faraz Ahmed

18. Limitations of File-based Approach
Data dependence
File structure is defined in the program code.
Incompatible file formats
Programs are written in different languages, and so cannot easily access each others files.
Integrity Problems
Integrity constraints (e.g. account_balance > 0) became “buried” in program code rather than being stated explicitly
Hard to add new constraint or update existing one
File in the folder cannot keep such conditions
difficult to enforce/add/change consistency constraints in a file processing system
Faraz Ahmed

19. Limitations of File-based Approach
Fixed Queries/Proliferation of application programs
Programs are written to satisfy particular functions. Any new requirement needs a new program.
Data Redundancy and Inconsistency
Multiple file formats, and duplication of information in different files
Difficulty in Accessing Data
Need to write a new program for accessing new data
Faraz Ahmed

20. Database Approach
Overcomes problems associated with file-system based approach
Central repository of shared data
The database holds not only the data but also a description of the data.
Data dictionary, or metadata
A central location where data descriptions are stored.
Data about data
Program-data independence
Faraz Ahmed

21. Advantages of the Database Approach
Program-data independence
The separation of data descriptions from the application programs that use the data.
Allows the data to change without changing the application programs.
No or Planned data redundancy
Improved data consistency
Improved data sharing
Enforcement of standards
Faraz Ahmed

22. DBMS is a Package
Faraz Ahmed

23. Database Management System (DBMS)
DBMS is a software package that enables user to create and maintain databases. It facilitates:
Defining a database that involves specifying the data types, structures, and constraints for the data to be stored in the database.
Constructing a database which is the process of storing the data.
Manipulating a database such as functions of querying and sharing the database objects, updating the database, and generating reports from the data.
Database and DBMS software together constitute a database system.
Faraz Ahmed

24. Examples DBMS Oracle IBM DB2 Ingress Teradata MS SQL Server MS Access
MySQL etc.
Faraz Ahmed

25. Database Management System (DBMS) Features
A Software Package that enables users to define, create, maintain, and control access to the database.
Data Definition Language (DDL)
Data Manipulation Language (DML)
Control access:
Security, integrity, concurrent access, recovery, support for data communication, etc.
Utility services
File import/export, monitoring facilities, code generator, report writer, etc.
Support Ad Hoc queries
Faraz Ahmed

26. DBMS Architecture
Form Processing & Report Processing Applications are build by using VB, DOT Net
or PHP programming. Reports can be developed using Crystal Reports tool.
Query Processing can be managed by using vendors SQL tool or 3rd party tools such
As TOAD, SQL Developer
Faraz Ahmed

27. Data Accessing using DBMS
2-tiers & 3-tiers Architectures
Faraz Ahmed

28. Database Management System
A software system that is used to create, maintain, and provide controlled access to user databases
Order Filing
System
Central database
Contains employee,
order, inventory,
pricing, and
customer data
Invoicing
System
DBMS
Payroll
System
DBMS manages data resources like an operating system manages hardware resources
Faraz Ahmed

29. Database System Environment
Faraz Ahmed

30. DBMS Benefits Minimal data redundancy Consistency of data
Integration of data
Sharing of data
Ease of application development
Uniform security, privacy and integrity controls
Data accessibility and responsiveness
Reduced program maintenance
Data independence
Faraz Ahmed

31. DBMS related Applications
SQL
Forms/ Reports
Web/ Portal
GUI Client-Server (VB, C++, Java, Mobile)
SAP/ OracleApps
BI Applications (SAS, OracleWarehousing)
Case Tools (Toad Modeler, Enterprise Architect, VISIO etc)
Faraz Ahmed

32. Components of DBMS Environment
Faraz Ahmed

33. Components of DBMS Environment
Hardware
Can range from a PC to a network of computers
Software
DBMS, operating system, network software (if necessary) and also the application programs
Data
Used by the organization and a description of this data called schema
Faraz Ahmed

34. Components of DB Environment …
Procedures
Instructions and rules that should be applied to the design and use of the database and DBMS
People
Faraz Ahmed

35. Database Professionals
Database implementers
Build modules that go inside the DBMS
Database application developers
Build application that run on top of the DBMS, and are used by end-users to interact with their data.
Database Administrators
Create database schema
Maintain and tune the DBMS engine
Maintain and tune the data in the DBMS
Corporations need them ($$$)
Faraz Ahmed

36. Roles/ Jobs in the Database Environment
Data Administrator (DA)
Database Administrator (DBA)
Database Designers (Logical and Physical)
Applications Programmer
Database Developer
Database Analyst
End users (Naive and sophisticated)
Faraz Ahmed

37. Forms & Reports Faraz Ahmed
Any data entry activity with data insert, update, search and delete constitutes a concept of Form.
Forms can be developed using VB Dot Net, Dot Net, Oracle Form Developers S/W
Reports: Read only, print purposes and no data change (open in pdf). Examples: Electric/ gas bills, degree transcript and automatic letter generated. Report development programming can be managed using Dot Net, Crystal Report, Oracle Report Developers S/W visual software programming.
Faraz Ahmed

38. -- Database Approach User 1 DBMS User 2 Application programs Database
Faraz Ahmed

39. Interaction of DBMS with Files
Faraz Ahmed

40. Evolution of DB Systems
Faraz Ahmed