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Slide 1Module I: Modern Information Systems
Data, Information, Knowledge, Data Resource Management: Introduction to DBMS, Benefits of DBMS over traditional file system, Types of DBMS, Application of DBMS using MS-ACCESS / ORACLE as a tool for understanding of DBMS concepts. SQL Query handling , Forms, Concept of Data Warehouses and Data Marts, Introduction to Data Centers
© 2006 Prentice Hall, Inc.
CBIS Components
History of Information System
Why Study Information Systems?
© 2006 Prentice Hall, Inc.
Amity Business School
Data vs. Information
Data consists of raw facts (i.e., a list of the numbers)
Information is a collection of facts organized (or processed) in such a way that they have additional value (i.e., a list of the class grades based on the exam score
In a way, information is data that has been transformed into a more useful form
Turning data into information is a process performed to achieve a defined outcome and requires knowledge
© 2006 Prentice Hall, Inc.
Data
Data are raw facts and figures that on their own have no meaning
These can be any alphanumeric characters i.e. text, numbers, symbols
© 2006 Prentice Hall, Inc.
42, 63, 96, 74, 56, 86
111192, 111234
None of the above data sets have any meaning until they are given a CONTEXT and PROCESSED into a useable form
© 2006 Prentice Hall, Inc.
Amity Business School
Data Into Information
To achieve its aims the organisation will need to process data into information.
Data needs to be turned into meaningful information and presented in its most useful format
Data must be processed in a context in order to give it meaning
© 2006 Prentice Hall, Inc.
Information
Data that has been processed within a context to give it meaning
OR
Data that has been processed into a form that gives it meaning
© 2006 Prentice Hall, Inc.
Example 1
Yes, Yes, No, Yes, No, Yes, No, Yes, No, Yes, Yes
Raw Data
Context
Responses to the market research question – “Would you buy brand x at price y?”
Information
Jayas scores in the six AS/A2 ICT modules
???
111192, 111234
???
Knowledge is the understanding of rules needed to interpret information
“…the capability of understanding the relationship between pieces of information and what to actually do with the information”
© 2006 Prentice Hall, Inc.
Using the 3 previous examples:
A Marketing Manager could use this information to decide whether or not to raise or lower price y
Jayas teacher could analyse the results to determine whether it would be worth her re-sitting a module
Looking at the pattern of the customer’s previous gas bills may identify that the figure is abnormally low and they are fiddling the gas meter!!!
© 2006 Prentice Hall, Inc.
Data – raw facts and figures
Information – data that has been processed (in a context) to give it meaning
© 2006 Prentice Hall, Inc.
Time
Location
Form
Individuals - Entertainment and enlightenment
2
Amity Business School
An information system is a system which assembles, stores, processes, and delivers information relevant to an organization (or to society) in such a way that the information is accessible and useful to those who wish to use it, including managers, staff, clients, and citizens.
An information system is a human activity (social) system which may or may not involve the use of computer systems.
Information Systems
Amity Business School
An information systems is a collection of components that collects, processes, stores, analyzes, and disseminates information for a specific purpose.
The major components of a computer-based information system (CBIS) can include (1) hardware, (2) software, (3) a database (4) a network (5 )procedures, and (6) people.
The system operates in a social context, and the software usually includes application programs which perform specific tasks for users.
© 2006 Prentice Hall, Inc.
Operational Level
Management Level
Strategic Level
Transaction Processing System
Management Information Systems
Decision Support Systems
Executive Support Systems
Office automation system
Knowledge management system
© 2006 Prentice Hall, Inc.
Transactions,
Events
Sorting,
Listing,
Merging,
Updating
Detailed
reports,
Lists,
summaries
EXAMPLE: GROCERY STORE CHECKOUT CASH REGISTER WITH CONNECTION TONETWORK, POS,ATM
POS,EPOS,VENDING MACHINES
Summary
© 2006 Prentice Hall, Inc.
Low volume data,
© 2006 Prentice Hall, Inc.
Aggregate data,
Projections, Responses to Queries
© 2006 Prentice Hall, Inc.
Amity Business School
Database systems were first developed in the 1960’s. They were then mostly used for business applications with large amounts of structured data, typically in the banking, insurance, and airline industries. Today, virtually all large corporations use database systems to keep track of customers, suppliers, reservations, orders, deliveries, invoices, employees, etc. As database systems became more
versatile, powerful, and user friendly, their use proliferated into a growing number of areas.
For example management information systems (MIS), decision
support systems (DSS), ad hoc query systems, inventory control systems, point
© 2006 Prentice Hall, Inc.
Bit: Smallest unit of data; binary digit (0,1)
Byte: Group of bits that represents a single character
Field: Group of words or a complete number
Record: Group of related fields
File: Group of records of same type
© 2006 Prentice Hall, Inc.
Amity Business School
The storage in which all data is kept in one or multiple locations, interconnected
by telecommunications.
A data base is the collection of interrelated non-redundant data stored to serve
multiple applications.
A Data base is a logically coherent collection of data with some inherent meaning.
A Data base is a collection of persistent data managed by a DBMS
© 2006 Prentice Hall, Inc.
Entity: Person, place, thing, event about which information is maintained
Attribute: Description of a particular entity
Key field: Identifier field used to retrieve, update, sort a record
File Organization Terms and Concepts (Continued)
© 2006 Prentice Hall, Inc.
2 What is a database?
The meaning of this term varies with the context. Any collection of data, such as
e.g. a file – electronic or otherwise – or a set of files, could possibly be called a
database, see Figure 1.
Figure 1 Without a database management system (DBMS) applications access files directly. This typically leads to duplication of data and/or
concurrency problems and/or inconsistent data. Applications are not protected from changes in file structures, i.e. little or no physical data independence is provided. The “database” is just an arbitrary collection of files with no centralized control
© 2006 Prentice Hall, Inc.
Amity Business School
A database is a persistent collection of data managed by a database management system (DBMS).
A DBMS is an agent whose job it is to manage a database; i.e. handle all database access and make sure the database is never corrupted, The following section gives a formal definition of what a DBMS is.
© 2006 Prentice Hall, Inc.
What is a database management system?
Database transaction, is a collection of read and/or write operations against one or more databases. The DBMS has to follow the basic rules like:
- Any not yet completed transaction can be undone
- No transaction is able to violate any integrity constraints defined for the
database
Concurrent transactions cannot interfere with each other
The effects of a completed transaction will indeed be reflected by the database, even if a hardware, software, or other failure should occur immediately”
after completion.
A DBMS IS AN INFORMATION STOAGE AND RETRIEVAL SYSTEM WHICH
PROVIDES ACID PROPERTIES FOR ALL DATA BASE TRANSACTIONS
© 2006 Prentice Hall, Inc.
1. Data Redundancy and Inconsistency:
Data redundancy: The presence of duplicate data in multiple data files so that the same data are stored in more than one place or location
Data inconsistency: The same attribute may have different values.
© 2006 Prentice Hall, Inc.
Amity Business School
The coupling of data stored in files and the specific programs required to update and maintain those files such that changes in programs require changes to the data
Lack of flexibility:
A traditional file system can deliver routine scheduled reports after extensive programming efforts, but it cannot deliver ad-hoc reports or respond to unanticipated information requirements in a timely fashion.
Program-data dependence:
© 2006 Prentice Hall, Inc.
Amity Business School
Because there is little control or management of data, management will have no knowledge of who is accessing or even making changes to the organization’s data.
Lack of data sharing and availability:
Information cannot flow freely across different functional areas or different parts of the organization. Users find different values of the same piece of information in two different systems, and hence they may not use these systems because they cannot trust the accuracy of the data.
Poor security:
© 2006 Prentice Hall, Inc.
Amity Business School
Software used to perform a number of operations on data base such as:
Adding new empty files to data base .
Inserting data into existing files.
Retrieving data from existing files.
Changing data in existing files.
Deleting data in the existing files.
Removing existing files from the data base.
© 2006 Prentice Hall, Inc.
Permits firms to rationally manage data for the entire firm
Acts as interface between application programs and physical data files
Separates logical and design views of data
Solves many problems of the traditional data file approach
© 2006 Prentice Hall, Inc.
1.Data
2.Hardware
3.Software
4.Users
1.DATA:
Data stored in a data base includes numerical data (integers or whole numbers)
or floating numbers and non numerical data (alphabets And numeric)
Logical (T/F), or data entities like pictures and images as data type.
DATA
INTEGRATED
SHARED
And storage.
3. SOFTWARE:
Between the physical database itself and the users of the system is a layer of software
called the DB Manager, or DB server or DBMS.
DBMS
DDL
DML
Using DDL, DML)
Data base Administrator
(A technical person responsible for implementing the data and maintaining the data base)
© 2006 Prentice Hall, Inc.
Amity Business School
Advantages Reduced data redundancy Reduced updating errors and increased consistency Greater data integrity and independence from applications programs Improved data access to users through use of host and query languages Improved data security Reduced data entry, storage, and retrieval costs Facilitated development of new applications program
© 2006 Prentice Hall, Inc.
Substantial hardware and software start-up costs
Damage to database affects virtually all applications programs
Extensive conversion costs in moving form a file-based system to a database system
Initial training required for all programmers and users
© 2006 Prentice Hall, Inc.
© 2006 Prentice Hall, Inc.
R elates data across tables based on common data element
Examples: DB2, Oracle, MS SQL Server
© 2006 Prentice Hall, Inc.
Supports one-to-many parent-child relationships
Hierarchical DBMS:
© 2006 Prentice Hall, Inc.
Network DBMS:
Lack support for ad-hoc and English language-like queries
Disadvantages:
Amity Business School
Object-oriented DBMS: Stores data and procedures as objects that can be retrieved and shared automatically
Object-relational DBMS: Provides capabilities of both object-oriented and relational DBMS
Object-Oriented Databases:
Centralized database:
Used by single central processor or multiple processors in client/server network
There are advantages and disadvantages to having all corporate data in one location.
Security is higher in central environments, risks lower.
If data demands are highly decentralized, then a decentralized design is less costly, and more flexible.
Distributing Databases
Databases can be decentralized either by partitioning or by replicating
Partitioned database: Database is divided into segments or regions. For example, a customer database can be divided into Eastern customers and Western customers, and two separate databases maintained in the two regions.
Distributed database:
Management
Data, Information, Knowledge, Data Resource Management: Introduction to DBMS, Benefits of DBMS over traditional file system, Types of DBMS, Application of DBMS using MS-ACCESS / ORACLE as a tool for understanding of DBMS concepts. SQL Query handling , Forms, Concept of Data Warehouses and Data Marts, Introduction to Data Centers
© 2006 Prentice Hall, Inc.
CBIS Components
History of Information System
Why Study Information Systems?
© 2006 Prentice Hall, Inc.
Amity Business School
Data vs. Information
Data consists of raw facts (i.e., a list of the numbers)
Information is a collection of facts organized (or processed) in such a way that they have additional value (i.e., a list of the class grades based on the exam score
In a way, information is data that has been transformed into a more useful form
Turning data into information is a process performed to achieve a defined outcome and requires knowledge
© 2006 Prentice Hall, Inc.
Data
Data are raw facts and figures that on their own have no meaning
These can be any alphanumeric characters i.e. text, numbers, symbols
© 2006 Prentice Hall, Inc.
42, 63, 96, 74, 56, 86
111192, 111234
None of the above data sets have any meaning until they are given a CONTEXT and PROCESSED into a useable form
© 2006 Prentice Hall, Inc.
Amity Business School
Data Into Information
To achieve its aims the organisation will need to process data into information.
Data needs to be turned into meaningful information and presented in its most useful format
Data must be processed in a context in order to give it meaning
© 2006 Prentice Hall, Inc.
Information
Data that has been processed within a context to give it meaning
OR
Data that has been processed into a form that gives it meaning
© 2006 Prentice Hall, Inc.
Example 1
Yes, Yes, No, Yes, No, Yes, No, Yes, No, Yes, Yes
Raw Data
Context
Responses to the market research question – “Would you buy brand x at price y?”
Information
Jayas scores in the six AS/A2 ICT modules
???
111192, 111234
???
Knowledge is the understanding of rules needed to interpret information
“…the capability of understanding the relationship between pieces of information and what to actually do with the information”
© 2006 Prentice Hall, Inc.
Using the 3 previous examples:
A Marketing Manager could use this information to decide whether or not to raise or lower price y
Jayas teacher could analyse the results to determine whether it would be worth her re-sitting a module
Looking at the pattern of the customer’s previous gas bills may identify that the figure is abnormally low and they are fiddling the gas meter!!!
© 2006 Prentice Hall, Inc.
Data – raw facts and figures
Information – data that has been processed (in a context) to give it meaning
© 2006 Prentice Hall, Inc.
Time
Location
Form
Individuals - Entertainment and enlightenment
2
Amity Business School
An information system is a system which assembles, stores, processes, and delivers information relevant to an organization (or to society) in such a way that the information is accessible and useful to those who wish to use it, including managers, staff, clients, and citizens.
An information system is a human activity (social) system which may or may not involve the use of computer systems.
Information Systems
Amity Business School
An information systems is a collection of components that collects, processes, stores, analyzes, and disseminates information for a specific purpose.
The major components of a computer-based information system (CBIS) can include (1) hardware, (2) software, (3) a database (4) a network (5 )procedures, and (6) people.
The system operates in a social context, and the software usually includes application programs which perform specific tasks for users.
© 2006 Prentice Hall, Inc.
Operational Level
Management Level
Strategic Level
Transaction Processing System
Management Information Systems
Decision Support Systems
Executive Support Systems
Office automation system
Knowledge management system
© 2006 Prentice Hall, Inc.
Transactions,
Events
Sorting,
Listing,
Merging,
Updating
Detailed
reports,
Lists,
summaries
EXAMPLE: GROCERY STORE CHECKOUT CASH REGISTER WITH CONNECTION TONETWORK, POS,ATM
POS,EPOS,VENDING MACHINES
Summary
© 2006 Prentice Hall, Inc.
Low volume data,
© 2006 Prentice Hall, Inc.
Aggregate data,
Projections, Responses to Queries
© 2006 Prentice Hall, Inc.
Amity Business School
Database systems were first developed in the 1960’s. They were then mostly used for business applications with large amounts of structured data, typically in the banking, insurance, and airline industries. Today, virtually all large corporations use database systems to keep track of customers, suppliers, reservations, orders, deliveries, invoices, employees, etc. As database systems became more
versatile, powerful, and user friendly, their use proliferated into a growing number of areas.
For example management information systems (MIS), decision
support systems (DSS), ad hoc query systems, inventory control systems, point
© 2006 Prentice Hall, Inc.
Bit: Smallest unit of data; binary digit (0,1)
Byte: Group of bits that represents a single character
Field: Group of words or a complete number
Record: Group of related fields
File: Group of records of same type
© 2006 Prentice Hall, Inc.
Amity Business School
The storage in which all data is kept in one or multiple locations, interconnected
by telecommunications.
A data base is the collection of interrelated non-redundant data stored to serve
multiple applications.
A Data base is a logically coherent collection of data with some inherent meaning.
A Data base is a collection of persistent data managed by a DBMS
© 2006 Prentice Hall, Inc.
Entity: Person, place, thing, event about which information is maintained
Attribute: Description of a particular entity
Key field: Identifier field used to retrieve, update, sort a record
File Organization Terms and Concepts (Continued)
© 2006 Prentice Hall, Inc.
2 What is a database?
The meaning of this term varies with the context. Any collection of data, such as
e.g. a file – electronic or otherwise – or a set of files, could possibly be called a
database, see Figure 1.
Figure 1 Without a database management system (DBMS) applications access files directly. This typically leads to duplication of data and/or
concurrency problems and/or inconsistent data. Applications are not protected from changes in file structures, i.e. little or no physical data independence is provided. The “database” is just an arbitrary collection of files with no centralized control
© 2006 Prentice Hall, Inc.
Amity Business School
A database is a persistent collection of data managed by a database management system (DBMS).
A DBMS is an agent whose job it is to manage a database; i.e. handle all database access and make sure the database is never corrupted, The following section gives a formal definition of what a DBMS is.
© 2006 Prentice Hall, Inc.
What is a database management system?
Database transaction, is a collection of read and/or write operations against one or more databases. The DBMS has to follow the basic rules like:
- Any not yet completed transaction can be undone
- No transaction is able to violate any integrity constraints defined for the
database
Concurrent transactions cannot interfere with each other
The effects of a completed transaction will indeed be reflected by the database, even if a hardware, software, or other failure should occur immediately”
after completion.
A DBMS IS AN INFORMATION STOAGE AND RETRIEVAL SYSTEM WHICH
PROVIDES ACID PROPERTIES FOR ALL DATA BASE TRANSACTIONS
© 2006 Prentice Hall, Inc.
1. Data Redundancy and Inconsistency:
Data redundancy: The presence of duplicate data in multiple data files so that the same data are stored in more than one place or location
Data inconsistency: The same attribute may have different values.
© 2006 Prentice Hall, Inc.
Amity Business School
The coupling of data stored in files and the specific programs required to update and maintain those files such that changes in programs require changes to the data
Lack of flexibility:
A traditional file system can deliver routine scheduled reports after extensive programming efforts, but it cannot deliver ad-hoc reports or respond to unanticipated information requirements in a timely fashion.
Program-data dependence:
© 2006 Prentice Hall, Inc.
Amity Business School
Because there is little control or management of data, management will have no knowledge of who is accessing or even making changes to the organization’s data.
Lack of data sharing and availability:
Information cannot flow freely across different functional areas or different parts of the organization. Users find different values of the same piece of information in two different systems, and hence they may not use these systems because they cannot trust the accuracy of the data.
Poor security:
© 2006 Prentice Hall, Inc.
Amity Business School
Software used to perform a number of operations on data base such as:
Adding new empty files to data base .
Inserting data into existing files.
Retrieving data from existing files.
Changing data in existing files.
Deleting data in the existing files.
Removing existing files from the data base.
© 2006 Prentice Hall, Inc.
Permits firms to rationally manage data for the entire firm
Acts as interface between application programs and physical data files
Separates logical and design views of data
Solves many problems of the traditional data file approach
© 2006 Prentice Hall, Inc.
1.Data
2.Hardware
3.Software
4.Users
1.DATA:
Data stored in a data base includes numerical data (integers or whole numbers)
or floating numbers and non numerical data (alphabets And numeric)
Logical (T/F), or data entities like pictures and images as data type.
DATA
INTEGRATED
SHARED
And storage.
3. SOFTWARE:
Between the physical database itself and the users of the system is a layer of software
called the DB Manager, or DB server or DBMS.
DBMS
DDL
DML
Using DDL, DML)
Data base Administrator
(A technical person responsible for implementing the data and maintaining the data base)
© 2006 Prentice Hall, Inc.
Amity Business School
Advantages Reduced data redundancy Reduced updating errors and increased consistency Greater data integrity and independence from applications programs Improved data access to users through use of host and query languages Improved data security Reduced data entry, storage, and retrieval costs Facilitated development of new applications program
© 2006 Prentice Hall, Inc.
Substantial hardware and software start-up costs
Damage to database affects virtually all applications programs
Extensive conversion costs in moving form a file-based system to a database system
Initial training required for all programmers and users
© 2006 Prentice Hall, Inc.
© 2006 Prentice Hall, Inc.
R elates data across tables based on common data element
Examples: DB2, Oracle, MS SQL Server
© 2006 Prentice Hall, Inc.
Supports one-to-many parent-child relationships
Hierarchical DBMS:
© 2006 Prentice Hall, Inc.
Network DBMS:
Lack support for ad-hoc and English language-like queries
Disadvantages:
Amity Business School
Object-oriented DBMS: Stores data and procedures as objects that can be retrieved and shared automatically
Object-relational DBMS: Provides capabilities of both object-oriented and relational DBMS
Object-Oriented Databases:
Centralized database:
Used by single central processor or multiple processors in client/server network
There are advantages and disadvantages to having all corporate data in one location.
Security is higher in central environments, risks lower.
If data demands are highly decentralized, then a decentralized design is less costly, and more flexible.
Distributing Databases
Databases can be decentralized either by partitioning or by replicating
Partitioned database: Database is divided into segments or regions. For example, a customer database can be divided into Eastern customers and Western customers, and two separate databases maintained in the two regions.
Distributed database:
Management