What is information?
Information is everywhere in an organization.
Information is stored in databases
Database – maintains information about various types of objects (inventory), events (transactions), people (employees), and places (warehouses)
Database models include:
1)Hierarchical database model – information is organized into a tree-like structure (using parent/child relationships) in such a way that it cannot have too many relationships.
2)Network database model – a flexible way of representing objects and their relationships.
3)Relational database model – stores information in the form of logically related two-dimensional tables.
Entity – a person, place, thing, transaction, or event about which information is stored
The rows in each table contain the entities
In Figure 7.1 CUSTOMER includes Dave’s Sub Shop and Pizza Palace entities
Attributes (fields, columns) – characteristics or properties of an entity class
The columns in each table contain the attributes
In Figure 7.1 attributes for CUSTOMER include Customer ID, Customer Name, Contact Name
Potential relational database for Coca-Cola
Primary keys and foreign keys identify the various entity classes (tables) in the database
Primary key – a field (or group of fields) that uniquely identifies a given entity in a table
Foreign key – a primary key of one table that appears an attribute in another table and acts to provide a logical relationship among the two tables
Database advantages from a business perspective include:
1)Increased flexibility
2)Increased scalability and performance
3)Reduced information redundancy
4)Increased information integrity (quality)
5)Increased information security
A well-designed database should:
1)Handle changes quickly and easily
2)Provide users with different views
3)Have only one physical view.Physical view – deals with the physical storage of information on a storage device
4)Have multiple logical views
5)Logical view – focuses on how users logically access information
A database must scale to meet increased demand, while maintaining acceptable performance levels
Scalability – refers to how well a system can adapt to increased demands
Performance – measures how quickly a system performs a certain process or transaction
Databases reduce information redundancy
Redundancy – the duplication of information or storing the same information in multiple places
Inconsistency is one of the primary problems with redundant information
information integrity measures the quality of information.
integrity constraint is the rules that help ensure the quality of information.
1)Relational integrity constraint
2)Business-critical integrity constraint
Information is the organizational asset and must be protected.
There have several databases security features:
1) Password : provides authentication of the user
2) Access level : determines who has access to the different types of information.
3) Access control : determines types of user access,such as read-only access,
Database management systems (DBMS) – software through which users and application programs interact with a database
Data-driven Web sites – an interactive Web site kept constantly updated and relevant to the needs of its customers through the use of a database
Data-driven web site business advantages :
1)Development
2)Content management
3)Future expandability
4)Minimizing human error
5)Cutting production and update costs
6)More efficient
7)Improved stability
Data driven business intelligence:
BI in data-driven web site
Integrating information among multiple databases:
Integration- allows separate systems to communicate directly with each other.
1) Forward integration : takes information entered into a given system and sends it automatically to all downstream systems and processes.
2) Backward integration- takes information entered into a given system and sends it automatically to all upstream systems and processes.
Forward integration:
Backward integration:
Building a central repository specifically for integrated information
Tuesday, 4 February 2014
Chapter 7 : Storing Organizational Information
Posted by Unknown at 20:21
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