Chapter 7 - Storing
Organizational Information - Database
RELATIONAL DATABASE FUNDAMENTALS
- Information is everywhere in an organization
- Information is stored in
databases
Ø
Database – maintains information
about various types of objects (inventory), events (transactions), people
(employees), and places (warehouses)
- Database models include;
Ø
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.
Ø Network database model – a flexible way of
representing objects and their relationships
Ø Relational
database model – stores information in the form of logically related
two-dimensional tables
ENTITIES AND ATTRIBUTES
- Entity
– a person, place, thing, transaction, or event about which information is
stored
Ø
The rows in each table contains
the entities
- Attributes
(fields, columns) – characteristics or properties of an entity class
Ø
The columns in each table contain
the attributes
KEYS AND RELATIONSHIPS
- Primary
keys and foreign keys identity the various entity classes (tables) in the
database
Ø
Primary key – a fields (or group
of fields) that uniquely identities a given entity in a table
Ø
Foreign key – a primary key of
one table that appears an attribute in another table and acts to provide a
logical relationships among the two tables
RELATIONAL DATABASE ADVANTAGES
- Database
advantages from a business perspective include;
Ø
Increased flexibility
Ø
Increased scalability and
performance
Ø
Reduced information redundancy
Ø
Increased information integrity
(quality)
Ø
Increased information security
INCREASED FLEXIBILITY
- A
well-designed database should;
Ø
Handle changes quickly and easily
Ø
Provide users with different
views
Ø
Have only one physical views
§
Physical view – deals with the
physical storage of information on a storage device
Ø
Have multiple logical views
§
Logical view – focuses on how
users logically access information
INCREASED SCALABILITY AND
PERFORMANCE
- A
database must scale to meet increased demand, while maintaining acceptable
performance levels
Ø
Scalability – refers to how well
a system can adapt to increased demands
Ø
Performance – measures how
quickly a system performs a certain process or transaction
REDUCED INFORMATION REDUNDANCY
- Databases
reduce information redundancy
Ø
Redundancy – the duplication of
information or storing the same information in multiple places
- Inconsistency
is one of the primary problems with redundant information
INCREASED INFORMATION SECURITY
- Information
is an organization asset and must be protected
- Databases
offer several security features including;
Ø
Password – provides
authentication of the user
Ø
Access level – determines who has
access to the different types of information
Ø
Access control – determines types
of user access, such as read-only access
DATABASE MANAGEMENT SYSTEMS
- Database
management systems (DBMS) – software through which users and application
programs interact with a database
DATA-DRIVEN WEB SITES
- Data-driven
Web sites – an interactive Web site kept constantly updated and relevant to the
needs of its customers through the use of database
DATA-DRIVEN WEB SITE BUSINESS
ADVANTAGES
- Development
- Content Management
- Future Expandability
- Minimizing Human Error
- Cutting Production and Update Costs
- More Efficient
- Improved Stability
DATA-DRIVEN BUSINESS INTELLIGENT
- BI in a data-driven Web site
INTEGRATING INFORMATION AMONG
MULTIPLE DATABASES
- Integration
– allows separate systems to communicate directly with each other
Ø
Forward integration – takes
information entered into a given system and sends it automatically to all downstream
systems and processes
Ø
Backward integration – takes
information entered into a given system and sends it automatically to
all upstream systems and processes
-
Building a central repository
specifically for integrated information
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