technology guide 3 data & database. agenda definition file processing problems database...
TRANSCRIPT
Technology Guide 3
Data & Database
Agenda
• Definition
• File processing problems
• Database
• Selection criteria
Definition
• Element– Bit, byte, field, record, file, database– Entity, attribute, key field
• Organization & access method– Sequential file– Indexed sequential file– Direct or random file
Agenda
• Definition
• File processing problems
• Database
• Selection criteria
File Processing Problems
• Redundancy
• Inconsistency
• Isolation
• Security
• Integrity
• Data/program independence
Agenda
• Definition
• File processing problems
• Database
• Selection criteria
Database
• Types
• Structure
• Models
• Creation
• Topology
Database Types
• Business database• Geographical information database• Knowledge database / deductive database• Multimedia database• Data warehouse• Data marts• Multimedia and hypermedia database• Object-oriented database
Database Structure
• Data definition language– Schema & subschema
• Data Manipulation language– Structured Query Language (SQL)– Query By Example (QBE)
• Data dictionary
Database Models• Hierarchical
– One to many– Usage
• Network– Many to many– Usage
• Relational– Normalization– Usage
• Object-oriented– Usage
Database Creation
• Conceptual design– Logical view– Entity-relationship (ER) diagram
• Entity, entity classes, instance, attributes, identifier
• Relationships, binary relationships
– Normalization
Database Creation
• Physical design– Physical view– Data topology (organization)
• Centralized• Distributed database
– Replicated database– Partitioned
– Access method– Security
Agenda
• Definition
• File processing problems
• Database
• Selection criteria
Selection Criteria
• User’ needs (type of application)• Compatibility• Portability• Reliability• Cost• Feature• Performance• Vendor’s support• Others?
Points to Remember
• Definition
• File processing problems
• Database
• Selection criteria
Discussion Question
• How can a database help an organization?
• Why normalization is very important for building a database?
• What kind of database model(s) is most suitable for E-bay?
• Do you see any problem(s) of the database in your organization?
Assignment
• Review technology guides 1-3
• Read technology guide 4, chapter 1
• Group Assignment
• Research paper