410 likes | 562 Views
Chapter 1: The Database Environment. Database. 1258369655710014 0025384102283991 9304522198620471 DATA. Database. Database. INFORMATION. Metadata. Field Name: MasterCardNum Field Type: Text Field Size: 19 Field Description: Unique identifier for each MasterCard Customer. Database.
E N D
Chapter 1: The Database Environment Database
1258369655710014 • 0025384102283991 • 9304522198620471 • DATA Database
Database INFORMATION
Metadata • Field Name: MasterCardNum • Field Type: Text • Field Size: 19 • Field Description: Unique identifier for each MasterCard Customer Database
Entities • Customer • Product • Employee • Invoice • Department • Entities Become Tables Database
Enterprise Data Model Customer Product Places Has Database Is Placed by Order Inventory Contains Is Contained In
Customer • LastName • FirstName • Address • City • State • Zip • Attributes are field names Database
Homework • Zero Tolerance Policy • Lab Assignment • Lecture Assignment Database
Enterprise Data Model • General Information • Overall Picture of Organization • Top-Down Approach Database
Information Systems Architecture Six key components: • Data • Processes • Network • People • Events / point of time • Reasons Database
Information Engineering Four Main Steps: • Planning • Analysis • Design • Implementation Database
Information Engineering Planning Phases 3 Steps: • Identify strategic planning factors • Identify corporate planning objects • Develop enterprise model Database
Identify Strategic Planning Factors • Goals • Mission statement • Corporate Vision • Critical success factors • Problem areas Database
Identify Corporate Planning Objects • Organizational units • Organizational locations • Business functions • Entity types • Information systems Database
Develop Enterprise Model • Functional Decomposition • Entity-relationship diagram • Planning Matrix (traceable information) Database
SDLC • Project Identification & Selection • Project Initiation & Planning • Analysis • Logical Design • Physical Design • Implementation • Maintenance Database
SDLC • Pretty • Paula • Always • Lets • People • Imitate • Me Database
Chapter 3: Entity-Relationship Model Database
Data Modeling Importance 3 Reasons: • Data Integrity • Data is central role of Information System • Stable information Database
Entity • Name of database table • All Caps • In rectangle • Noun • Singular Database ENTITY
Weak Entity EMPLOYEE Database Has DEPENDENT
Relationship • Diamond • Verb • Shows action • Capital Letter followed by lower case • Must connect to Entity Relationship Database
Relationship Cardinality Mandatory One Mandatory Many Database Optional One Optional Many
Relationship Degrees Binary Unary Database Ternary
Attribute • Characteristic of entity • Oval Shape • Singular • Capital Letter followed by lower case • Primary Key is underlined • Field names of table Database Attribute
Attribute Types Attribute Database Multivalued Attribute Derived Attribute
Composite Attribute Address Database EmployeeID EmployeeName EMPLOYEE
Cardinality Constraints • Minimum cardinality -smallest amount of relationships between the two entities • Maximum cardinality -largest amount of relationships between the two entities Database
Chapter 4: Enhanced ER Model Database
Subtypes UNDERGRADUATE d Database FRESHMEN JUNIOR SOPHOMORE SENIOR
Generalization • Bottom-Up Process • Take a general entity with common attributes • Define specific attributes for each subtype Database
Specialization • Top-Down Process • Take a very specialized entity with all of its attributes • Define distinct attributes for each subtype Database
Total Specialization Double line connecting entity to subtype circle Either one subtype or the other subtype Partial Specialization Single line connecting entity to subtype circle Partial overlap but not completely the same subtypes Completeness Constraints Database
Disjoint Rule Either an entity is one type or another subtype at this point in time Place a “d” in subtype circle Overlap Rule An entity can be both subtypes in one point in time Place a “o” in subtype circle Disjointness Constraints Database
Subtype Discriminator • An attribute of an entity which defines which subtype this instance belongs to • Place a definition beside subtype circle • Place discriminator in quotation marks above each subtype relationship Database
Root Main entity at the top of a hierarchy For example: • Page 140-PATIENT • Page 141-EMPLOYEE • Page 142-PART • Page 144-PERSON Database
Business Rules Unique business rules which apply to a specific organizations’ database Two Types: • Structural constraints • Operational constraints Database
Structural Constraints • Derived Facts Defined in repository Built into the database • Example Page 149 ER Diagram similar to your project Database
Operational Constraints • Collection of rules inside the repository • One relationship constricts the actions of another relationship Database R