v Relational
Database Fundamentals
v Information
is everywhere in an organization
v Information
is stored in databases
§ Database
– maintains information about various types of objects (inventory), events
(transactions), people (employees), and places (warehouses)
Relational Database Fundamentals
v 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
v Entity
– a person, place, thing, transaction, or event about which information is
stored
§ The
rows in each table contain the entities
§ Attributes
(fields, columns) – characteristics or properties of an entity class
§ The
columns in each table contain the attributes
Keys and Relationships
v 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
Keys and Relationships
v Potential
relational database for Coca-Cola
Relational Database Advantages
v 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
v A
well-designed database should:
§ Handle
changes quickly and easily
§ Provide
users with different views
§ Have
only one physical view
•
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
v 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
v Databases
reduce information redundancy
§ Redundancy
– the duplication of information or storing the same information in multiple
places
v Inconsistency
is one of the primary problems with redundant information
Increase Information Integrity (Quality)
v Information
integrity – measures the quality of information
v Integrity
constraint – rules that help ensure the quality of information
§ Relational
integrity constraint
§ Business-critical
integrity constraint
Increased Information Security
v Information
is an organizational asset and must be protected
v 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
v Database
management systems (DBMS) – software through which users and
application programs interact with a database
DATA-DRIVEN WEB SITES
v 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
v Development
v Content
Management
v Future
Expandability
v Minimizing
Human Error
v Cutting
Production and Update Costs
v More
Efficient
v Improved
Stability
Data-Driven Business Intelligence
v BI
in a data-driven Web site
Integrating
Information
v 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
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