RELATIONAL DATABASE FUNDAMENTALS
- 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;
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.
Network database model – a flexible way of
representing objects and their relationships
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
The rows in each table contains the entities
- Attributes
(fields, columns) – characteristics or properties of an entity class
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
Primary key – a fields (or group of fields) that
uniquely identities 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
relationships among the two tables 
RELATIONAL DATABASE ADVANTAGES
- Database
advantages from a business perspective include;
Increased flexibility
Increased scalability and performance
Reduced information redundancy
Increased information integrity (quality)
Increased information security
INCREASED FLEXIBILITY
- A well-designed
database should;
Handle changes quickly and easily
Provide users with different views
Have only one physical views
Physical view – deals with the physical storage
of information on a storage device
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
Scalability – refers to how well a system can
adapt to increased demands
Performance – measures how quickly a system
performs a certain process or transaction
REDUCED INFORMATION REDUNDANCY
- 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
INCREASED INFORMATION SECURITY
- Information is
an organization asset and must be protected
- Databases offer several security features
including;
Password – provides authentication of the user
Access level – determines who has access to the
different types of information
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
- Forward integration – takes information entered into a given system and sends it automatically to all downstream systems and processes
- 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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