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.
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
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