😍 Information is everywhere in an organization.
😍 Information is stored in databases
- Database - maintain information about various types of objects (inventory), events (transactions), people (employees), and places (warehouses)
- 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.
😍 Entity - a person, place, thing, transaction, or event about which information is stored
- the row in each table contain entities
😍 Attributes - characteristics or properties of an entity class
- the colums in each table contain attributes
KEYS AND RELATIONSHIPS
😍 Primary key - a field (or group of fields) that uniquely identifies a given entity in table
😍 Foreign key - a primary key of one table that appears an attribute in another table and acts to provide a logical relationship among two tables
Relational Database Advantages
- increased flexibility
💚 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
😍 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
💚 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 integrity (quality)
😍 Integrity constraint – rules that help ensure the quality of information
💚Relational integrity constraint
💚Business-critical integrity constraint
- increased information security
😍 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 SYSTEM
😍 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 a 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 Intelligence
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
THE END OF CHAPTER 7 💙
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