Database
Content
Database Management
Objective
This course is designed to give a
1. Thorough
understanding
of
databases. databases. 2. It enables students to practically deal with database related issues on the basis of solid concepts and theory. theory.
Industrial Scope
Dataware housing Ebanking Police Criminal record NADRA Datamining FIA database Macodonalds
Contents (Summary)
Concepts of Database Management Database Designing and Modelling ClientClient-Server Architecture, Data Dictionaries SQL
DDL,DML,Views ,Constraints
Oracle SQL Distributed Database Object oriented database Database Administration
Key to success
Punctuality Hard work Practice Devotion Dedication
What is Data ?
Definition of Data
Data consists of Facts, text, graphics, images, sound and video segments that have meaning to user¶s environment. Data can exist in a variety of forms: - As numbers or text on pieces of paper - As bits and bytes stored in electronic memory - As facts stored in a person's mind.
Data Type
Data is what we measure Data type refers to the classification of a particular type of information integer floating point character, string date student record blob (binary large object)
Data in Context
Large volume of facts, difficult to interpret or make decisions based on
INFORMATION Data that has been processed in such a way that it can increase the knowledge of person who uses it
Useful information that managers can use for decision making and interpretation
Data vs Information
Data into information
Summarise data Data In context (table) Decision support
We use Database term without distinguish data or information
ACTIVITY
Please write down the data for cricket match bowling Do you get any information??
Definition of Database
³ Database is a shared collection of logically related data, designed to meet the information needs of multiple users in an organization ´ Database is designed, built, and populated with data for a specific purpose. It has an intended group of users and preconceived applications in which these users are interested.
Alternative Terminology
Data Processing Terms Formal Terms Relation Tuple Attribute Alternative 1 Table Row Column Alternative 2 File Record Field
Formal terms are mostly used for technical users. Data processing terms are more natural for non technical users.
Computerized File Based Processing System
Computerized File-based FileProcessing
File handling routines & File definition
Sales
Sales files
File handling routines & File definition
Contracts
Contracts files
FileFile-based Systems
A collection of application programs that perform services for the end users (e.g. reports). Each program defines and manages its own data.
Three file processing systems
Duplicate Data
Limitation of Computerized FileFilebased Approach
Separation and Isolation of data Each application maintains its own set of data. Users of one application may be unaware of potentially useful data held by other applications.
Duplication of data (data redundancy)
Same data is held by different files. No centralized control of data
Limited Data Sharing Lengthy Development Times
Programmers must design their own file formats
Excessive Program Maintenance
80% of information systems budget
Limitation of File-based FileApproach
Accessibility Data is stored using programs that are written in different languages and format Cannot easily access other files due to incompatible file format. No control over access and manipulation of data beyond that imposed by application programs. Hard Coded Queries (Data dependence) File structure and all definition of data are defined in the application program code. Programs are written to satisfy particular functions / requirements. Any new requirement needs a new program.
Problems with Data Dependency
Each application programmer must maintain
their own data Each application program needs to include code for the metadata of each file Each application program must have its own processing routines for reading, inserting, updating and deleting data Lack of coordination and central control NonNon-standard file formats
Problems with Data Redundancy
Waste of space to have duplicate data Causes more maintenance headaches The biggest Problem:
When data changes in one file, could cause inconsistencies Compromises data integrity
SOLUTION:
Database Processing System
Database Processing
Sales Application
Sales
DBMS
Database
Contracts Application
Contracts
The DATABASE Approach
Central repository of shared data Data is managed by a controlling agent Stored in a standardized, convenient form
Requires a Database Management System (DBMS)
Database Management System
Application #1
Application #2
DBMS
DBMS manages data resources like an operating system manages hardware resources
Database containing centralized shared data
Application #3
Database Management System (DBMS)
A collection of programs that enables users to define,create and maintain and control access to the database. General-purpose software system that facilitates the processes of defining, constructing and manipulating databases for various applications.
Defining - specifying data types, structures, constraints. Constructing - storing of data Manipulation - querying, updating and reporting.
Popular DBMS In The Market
Sybase SQL Anywhere
Informix Dynamic Server
Borland Interbase
Database Management System
A DBMS is a data storage and retrieval system which permits data to be stored nonnon-redundantly while making it appear to the user as if the data is wellwellintegrated.
Advantages of Database Approach
ProgramProgram-Data Independence
Metadata stored in DBMS, so applications don t need to worry about data formats Data queries/updates managed by DBMS so programs don t need to process data access routines Results in: increased application development and maintenance productivity
Minimal Data Redundancy
Leads to increased data integrity/consistency
Advantages of Database Approach Improved Data Sharing
Different users get different views of the data
Enforcement of Standards
All data access is done in the same way
Improved Data Quality
Constraints, data validation rules
Better Data Accessibility/ Responsiveness
Use of standard data query language (SQL)
Security, Backup/Recovery, Concurrency
Disaster recovery is easier
Costs and Risks of the Database Approach
UpUp-front costs:
Installation Management Cost and Complexity Conversion Costs Cost of DBMS Additional hardware costs.
Ongoing Costs:
Requires New, Specialized Personnel Need for Explicit Backup and Recovery Higher impact of a failure
Organizational Conflict:
Old habits die hard
The Range of Database Applications
Personal Database standalone desktop database Workgroup Database local area network (<25 users) users) Department Database local area network 25users) (25-100 users) Enterprise Database wide-area network wideusers) (hundreds or thousands of users)
Personal Computer Database
Workgroup database with local area network
An enterprise data warehouse
Components of DBMS Environment
1. Hardware Can range from a PC to a network of computers. 2. Software DBMS itself and operating system, including any network software if network is being used. 3. Data Includes actual data used by the organization, and description of data (schema). Also a system catalog contains data such as the names of authorized users.
Components of DBMS Environment
4. Procedures Instructions and rules that should be applied to the design and use of the database, and the use of the DBMS. 5. People Data & Database Administrator Database Designer :- Logical & Physical Application Programmers End Users
DBMS Environment
Bridge Data Software Hardware Machine Procedures People Human
Database System Environment
Users/Programs Application Programs/Queries
Software to Process Queries/Programs Software to Access Stored Data
Stored Database Definition
Stored Database
Evolution of DB Systems
Flat files - 1960s - 1980s Hierarchical 1970s - 1990s Network 1970s - 1990s Relational 1980s - present ObjectObject-oriented 1990s - present ObjectObject-relational 1990s - present Data warehousing 1980s present WebWeb-enabled 1990s - present
Summary
Course Contents Data Information Data Vs Information Database Terms DBMS Advantages Disadvantages of DBMS Database Terms Comparison of Computerized File Based Processing System & Database System
Objective
This course is designed to give a
1. Thorough
understanding
of
databases. databases. 2. It enables students to practically deal with database related issues on the basis of solid concepts and theory. theory.
Industrial Scope
Dataware housing Ebanking Police Criminal record NADRA Datamining FIA database Macodonalds
Contents (Summary)
Concepts of Database Management Database Designing and Modelling ClientClient-Server Architecture, Data Dictionaries SQL
DDL,DML,Views ,Constraints
Oracle SQL Distributed Database Object oriented database Database Administration
Key to success
Punctuality Hard work Practice Devotion Dedication
What is Data ?
Definition of Data
Data consists of Facts, text, graphics, images, sound and video segments that have meaning to user¶s environment. Data can exist in a variety of forms: - As numbers or text on pieces of paper - As bits and bytes stored in electronic memory - As facts stored in a person's mind.
Data Type
Data is what we measure Data type refers to the classification of a particular type of information integer floating point character, string date student record blob (binary large object)
Data in Context
Large volume of facts, difficult to interpret or make decisions based on
INFORMATION Data that has been processed in such a way that it can increase the knowledge of person who uses it
Useful information that managers can use for decision making and interpretation
Data vs Information
Data into information
Summarise data Data In context (table) Decision support
We use Database term without distinguish data or information
ACTIVITY
Please write down the data for cricket match bowling Do you get any information??
Definition of Database
³ Database is a shared collection of logically related data, designed to meet the information needs of multiple users in an organization ´ Database is designed, built, and populated with data for a specific purpose. It has an intended group of users and preconceived applications in which these users are interested.
Alternative Terminology
Data Processing Terms Formal Terms Relation Tuple Attribute Alternative 1 Table Row Column Alternative 2 File Record Field
Formal terms are mostly used for technical users. Data processing terms are more natural for non technical users.
Computerized File Based Processing System
Computerized File-based FileProcessing
File handling routines & File definition
Sales
Sales files
File handling routines & File definition
Contracts
Contracts files
FileFile-based Systems
A collection of application programs that perform services for the end users (e.g. reports). Each program defines and manages its own data.
Three file processing systems
Duplicate Data
Limitation of Computerized FileFilebased Approach
Separation and Isolation of data Each application maintains its own set of data. Users of one application may be unaware of potentially useful data held by other applications.
Duplication of data (data redundancy)
Same data is held by different files. No centralized control of data
Limited Data Sharing Lengthy Development Times
Programmers must design their own file formats
Excessive Program Maintenance
80% of information systems budget
Limitation of File-based FileApproach
Accessibility Data is stored using programs that are written in different languages and format Cannot easily access other files due to incompatible file format. No control over access and manipulation of data beyond that imposed by application programs. Hard Coded Queries (Data dependence) File structure and all definition of data are defined in the application program code. Programs are written to satisfy particular functions / requirements. Any new requirement needs a new program.
Problems with Data Dependency
Each application programmer must maintain
their own data Each application program needs to include code for the metadata of each file Each application program must have its own processing routines for reading, inserting, updating and deleting data Lack of coordination and central control NonNon-standard file formats
Problems with Data Redundancy
Waste of space to have duplicate data Causes more maintenance headaches The biggest Problem:
When data changes in one file, could cause inconsistencies Compromises data integrity
SOLUTION:
Database Processing System
Database Processing
Sales Application
Sales
DBMS
Database
Contracts Application
Contracts
The DATABASE Approach
Central repository of shared data Data is managed by a controlling agent Stored in a standardized, convenient form
Requires a Database Management System (DBMS)
Database Management System
Application #1
Application #2
DBMS
DBMS manages data resources like an operating system manages hardware resources
Database containing centralized shared data
Application #3
Database Management System (DBMS)
A collection of programs that enables users to define,create and maintain and control access to the database. General-purpose software system that facilitates the processes of defining, constructing and manipulating databases for various applications.
Defining - specifying data types, structures, constraints. Constructing - storing of data Manipulation - querying, updating and reporting.
Popular DBMS In The Market
Sybase SQL Anywhere
Informix Dynamic Server
Borland Interbase
Database Management System
A DBMS is a data storage and retrieval system which permits data to be stored nonnon-redundantly while making it appear to the user as if the data is wellwellintegrated.
Advantages of Database Approach
ProgramProgram-Data Independence
Metadata stored in DBMS, so applications don t need to worry about data formats Data queries/updates managed by DBMS so programs don t need to process data access routines Results in: increased application development and maintenance productivity
Minimal Data Redundancy
Leads to increased data integrity/consistency
Advantages of Database Approach Improved Data Sharing
Different users get different views of the data
Enforcement of Standards
All data access is done in the same way
Improved Data Quality
Constraints, data validation rules
Better Data Accessibility/ Responsiveness
Use of standard data query language (SQL)
Security, Backup/Recovery, Concurrency
Disaster recovery is easier
Costs and Risks of the Database Approach
UpUp-front costs:
Installation Management Cost and Complexity Conversion Costs Cost of DBMS Additional hardware costs.
Ongoing Costs:
Requires New, Specialized Personnel Need for Explicit Backup and Recovery Higher impact of a failure
Organizational Conflict:
Old habits die hard
The Range of Database Applications
Personal Database standalone desktop database Workgroup Database local area network (<25 users) users) Department Database local area network 25users) (25-100 users) Enterprise Database wide-area network wideusers) (hundreds or thousands of users)
Personal Computer Database
Workgroup database with local area network
An enterprise data warehouse
Components of DBMS Environment
1. Hardware Can range from a PC to a network of computers. 2. Software DBMS itself and operating system, including any network software if network is being used. 3. Data Includes actual data used by the organization, and description of data (schema). Also a system catalog contains data such as the names of authorized users.
Components of DBMS Environment
4. Procedures Instructions and rules that should be applied to the design and use of the database, and the use of the DBMS. 5. People Data & Database Administrator Database Designer :- Logical & Physical Application Programmers End Users
DBMS Environment
Bridge Data Software Hardware Machine Procedures People Human
Database System Environment
Users/Programs Application Programs/Queries
Software to Process Queries/Programs Software to Access Stored Data
Stored Database Definition
Stored Database
Evolution of DB Systems
Flat files - 1960s - 1980s Hierarchical 1970s - 1990s Network 1970s - 1990s Relational 1980s - present ObjectObject-oriented 1990s - present ObjectObject-relational 1990s - present Data warehousing 1980s present WebWeb-enabled 1990s - present
Summary
Course Contents Data Information Data Vs Information Database Terms DBMS Advantages Disadvantages of DBMS Database Terms Comparison of Computerized File Based Processing System & Database System
