Data Modeling and Relationship1
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1Introduction toEntities, Attributes, andRelationships
Conceptual Modeling : Entities, Attributes, Relationships Conceptual Modeling ? Entities Attributes Relationship
Modeling ? Conceptual Data Modeling Physical Data Modeling ? Entity Model Table ? ? Modeling , , Model
Conceptual Model ? System Physical Database Design
Conceptual Model Conceptual Model System (Sponsor) Model Design Physical Database
, Entities Relationship Diagram Table Database Object Model Model Business Tables Database ? Columns Tables ? Constraint Database Object (require) ? (Metaphor)
(Solid Plan) ? (Architect) (Architect) Model (Sketches) Conceptual Model (Easy Change) Model Model Design (Technical Design) Model Design
Entity Relationship Model Entity Relationship Modeling Model Business (Implement) Diagram
Modeling ?Entity Relationship Modeling Modeling Business Modeling Business System Model Business Business Entity Relationship Modeling Business Diagram (Check)
Entity Relationship Modeling Entity Relationship Modeling
Model Model
Conceptual Data Modeling Business Model (Implement) Model Entity Relationship model tables
Database
Database Flat file data model: Database Model Store File File Link File Model Redundancy Model Hierarchical data model: Database Model Database file Link Top Database Parent Database Parent Child Child Parent Child Database Parent Database File Link Pointer Model Network Data Model Database Model Hierarchical data model Link Child Database Redundant Data, Search Model Database Expert Model Real-Life ApplicationRelational Data Model Database Model Link Entity Business Redundant Data Normalization Search Data Index Attribute User (Implement) DBMS
Entities EntitiesEntity Business : (Object) , (Event) Entities Instances
Entity Entity Entity Entity Business Entity Business Entity (Class) (Type) Entity Entity instance Instance Entity Business
Entities (More on Entities)
Entity Instance : Entity Entity Instance Entity Person Product Require Skill Level Election Instance Entity Entity Violinist Instance Entity Job Violinist Entity Instance David Oistrach, Kyung-Wha Chung.
Entities (Sets)Entities (Sets) Entity Instance Business
Entity Job Instance Entity Modeling Process, Entity Table Row Table Instance Entity Modeling Properties Instance Entity
(Set Theory) Entity Relationship Model Relational Database
AttributesAttributes
(something) Business single valued Property Entity : (Describe) (Quantifies) (Qualifies) (Classifies) Entity
Attribute ? Attribute Entity Attribute Property Entity Entity Entity Attribute (Entities Have Attributes) Entity Attribute Attribute Entity (Values and Data Types)Attribute Attribute Attribute Attribute
Attribute Single ValuedAttribute Entity Single Valued Instance Entity Attribute Attribute Examples
Town of Residence Attribute Employee Attribute Attribute Single valued Shoes Size Attribute Business Business Attribute Family Name Attribute Single Valued
Volatile AttributesAttribute Volatile () Attribute Age Nonvolatile Attribute Attribute Birth Date Age
RelationshipsRelationships
Business Entity Entity
Entity Relationship
Relationship Entity Relationship (Dependency) Entity Relationship : An Employee has a JOB An Employee performs a JOB An Employee holds a JOBAn Employee apply for a JOB Relationship Entity Relationship
Instance Entity Employee JOB ? Mandatory Optional Relationship Employee? Employee JOB ? JOB Employee ? Mandatory Optional Relationship JOB? Job Employee ? () Design Table Entity Relationship Models DiagramsEntity Relationship Model (ER Model) Entity Attribute Relationship Model Entity Description, Data type Constraint Model Diagram Model Entity Relationship Diagram (ER Diagram) Model Model Model Diagram BusinessGraphical Elements
Entity Relationship diagramming Graphic Element ISO Standard ER Diagram Oracle Oracle diagramming technique Oracle Designer Tool
Entity
ER diagram Entity SoftBox Entity Entity Box Entity Box Entity Name Box Size Entity Entity Entity
Attribute (Attribute Representation)
Attribute Entity Box * O Attribute mandatory optional Attribute * Mandatory: Attribute Businesso Optional: Attribute Business Attribute Entity Diagram Attribute Design Table Attribute Diagram Attribute ? Design, Attribute Column Mandatory Attribute Not Null
RelationshipRelationship Entity Relationship Relationship Shape Relationship Degree Relationship One Many One Many
JOB Employee Employee JOB Relationship Relationship Diagram Model Model
Mandatory Optional RelationshipsRelationships mandatory optional attributes . Mandatory Relationships (solid line) optional relationships (dotted lines).Relationship Relationship Relationship Employee JOB Model optional relationship mandatory relationship
Relationship
Every EMPLOYEE has exactly one JOB or, alternatively:An EMPLOYEE must have exactly one JOB.
JOB EmployeeA JOB may be held by one or more EMPLOYEES.
Relationship
Relationship Entity1 Entity2 Each entity1{must be | may be} relationship_name {one or more | exactly one} entity2Relationship Design Relationship foreign key foreign key column optional relationship non mandatory foreign key columns Relationship Diagram Relationship Diagram space Diagram Relationship
(Data and Functionality)
Conceptual Data Model Conceptual Data Model Shoes Size Employee ? Business ?
(Type of Information)
? ? Kbenhavn, Bremen Icon Column City Name of the city (such as Kbenhavn) Weather type (such as cloudy with rain) Icon of the weather type Minimum temperature Maximum temperature Wind direction arrow Wind force Forecast date? Business (geographical knowledge)
German cities (Bremen, Berlin Munchen) French cities cities - Report (Next Step) Entity ? Attribute Relationship City Country Entity Attribute (Name ) Weather Type Wind Direction Entity Attribute (Icon, Description) City Entity Forecast Attribute (Date, Minimum and Maximum Temperature Wind Force) Relationship COUNTRY and CITY CITY and FORECAST FORECAST and WEATHER TYPE FORECAST and WIND DIRECTION
Entity Relationship Diagram Relationship FORECAST CITY CITIES FORECAST CITY COUNTRY COUNTRY CITY FORECAST WEATHER TYPE WEATHER TYPE FORECAST FORECAST WIN DIRECTION WIN DIRECTION FORECAST Graphical Elements (Other Graphical Elements)
Graphic Element ER Diagram Entity Attribute Relationship 4 Subtype Entity Entity Unique identifier # Attribute Relationship Arc Relationship Nontransferability symbol Relationship Graphical Elements Graphical Element ER Diagram ER Modeling (Representation) ER Modeling Business Entity, Attribute Relationship Business SummaryConceptual models Model Business Model model model data conceptual models (implementation)
Entity Relationship modeling ER model Data Model Entity Relationship diagrams Diagram ER model Diagram Business System
1-1 Entity, Attribute Instance Entity instance attribute instance Entity 3 Row concept
1-2 Entity : GUEST, HOTEL ROOM Attribute Attribute Entity Entity
1-3 Diagram?
1-41. relationships Model 2. Relationship
1-51. Relationship Model
2. Relationship PERSON HOTEL hotel business.
1-6 Recipe1. Ralphs famous Raving Recipes
2. Entity Attribute 3. relationships Diagram
2
Entities and Attributesin Detail
Entity Attribute Entity concept of subtype supertype entity Business ElectronicMail Inc
Data Information
Data Information (synonyms)
Data: Information: (Data)
(Data)
Conceptual Data Modeling
Conceptual data modeling Business Business Data Business Business DataPhysical Data Modeling
Physical data modeling Software Hardware Design 5
Database Electronic Electronic spreadsheets File Relational Database System System hierarchical databases network databasesSystem semantic databases object oriented databasesData WarehouseData warehouse Logical Database data warehouse database Online Analytical Processing (OLAP) Data warehouse (Transaction System) Call (Store) Call Call
Entity texts, notes, brochures screens Business entities, attribute entities Instance entities
Entity Entity Entity Entity Model Entity modeling process (Be Aware of Synonyms) Business ...also known as ... ( Avoid Homonyms) Business Reserved Words Entity Database Programming Relationship Entity Entity diagrams Model contex
Electronic MailBusiness Electronic Mail Email User
Electronic Mail (EM) Mail System User Web User Message User Email Address 30 Password Email Address User User User name, country, birth date, line of business User (Sent) (receive) Email Email Message Text Attach file Attach file File spreadsheet Message Message folders User Folder Inbox Outbox Wastebasket Folder User
Screenshots Compose Email Message Screen Maintain Addresses screen
User Electronic Mail Address Message Mail E-mail Address System Message ( Database ) Message User Template Message Template Message User Reply Message Reply, User Message Message User Alias Email Address
Entity Entity Electronic Mail Message Entity Message User
User ? Message EM User
message ? Message Attachment ?Message EM User Message (Text) (Subject)
Message (External Source) EM User ? ?Message EM User EM User Message (Text ) (Subject)
Message EM User Email Address EM User Email Message System Message Message EM UserMessage EM User Message (Text ) (Subject)
process Entity Life Cycle Life Cycle Entity Life cycle Entity Entity Instance ? ? ? Entity Message Message ? Message ? Message ? Message Compose Screen, Message ? Message Field To Subject Field Send Key Message System Message ? User Delete Key? System Receiver Message Message System Message Message Message ? Message Message ? Message ? Message (Draft) Message ? Draft Message Message ? Draft Message System ? Draft Entity Message ? DRAFT Entity ?Template Template ? Template Message Template Message Template Entity Message ? Entity Functionality Entity Functionality System Message System Function conceptual data model BusinessUser Electronic Mail Address Message Mail E-mail Address System Message Message User Create Template Message Template Message Template Message User Reply Message Reply User Create Message Message User Create (Alias) Email Address, Address Nickname
Functionality System Functionality Functionality high level Functionality
Attributes
Attribute ? ?Attribute describe, quantify, qualify, classify, specify Entity Attribute Property Entity Electronic Mail Entity Attribute Instance
Entity Attribute Attribute Name of COUNTRY Attribute instance Name of FOLDER
Attribute Attribute Column Column Attribute Reserved Word Id, No, Descr, Ind(icator) Attribute Amount, Value, Number Attribute Amount Paid, Estimated Value, Licence No Date Indicator Attribute at the endStart Date, Creation Date Purchase Date Underscores( _ ) Attribute Attribute Entity Entity Attribute Attribute Context Entity Context Attribute Name Model Entity Dimension language Acapulco swimming trunks Akapulko Badehose
Redundancy redundant attributes Attribute Attribute physical design decision Attribute Date Instance Created User Subtypes Supertypes Entity X Subtype Instances Property Attributes Relationships Attribute functionality Subtype Entity X Entity X SubpertypeSubtypes Model constraints Subtype
Subtype Property Entity X Supertype Address Subtype USER LIST USER LIST Attribute NAME To Field Message Inheritance Entity COMPOSITION Supertype MESSAGE, DRAFT TEMPLATE Subtypes Attribute Relationship Supertype Entity
Diagram Every MESSAGE (DRAFT, or TEMPLATE) is a COMPOSITIONEvery COMPOSITION is either a MESSAGE, a DRAFT, or a TEMPLATE
SubtypeEntity relationship modeling ER model Subtype Entity Subtype Subtype Entity Subtype ? Subtype
Nested Subtypes Subtype Subtype Subtype Level Attribute Relationship Level
Subtypes Entity Subtype Instance Subtype Business
Subtype (Implementing Subtypes) Subtype Entity Table Table Super entity (Summary)Entity Business Entity (Tangible), (Intangible) (Event) Subtypes Entity Attribute Relationship Entity
1. Book Entity publishing company book reseller Entity Book Entity Attribute
2. ER model Text Entity Entity Relationship1. Entity 15 Moonlight Coffees Summary
2. Entity The coffee shops. The Moonlight employees. ER Model
3Relationshipsin Detail
relationship Entity Relationship nontransferable relationships Relationship Attribute Relationship Attribute normalization conceptual models
Relationship (Establishing a Relationship)
Relationship Entity Entity Model Entity Model Entity Entity Electronic Mail System Relationship MESSAGE USER Message Message Entity recursive relationship Message Reply Message
Relationship perspective Passive is owner of is owned by parent of / child of composed of / part of Preposition , Relationship Consists of / is part of Is classified as / is classification for Is assigned to / is assignment of Is referred to / referring to Responsible for / the responsibility of with, in, of, for, by, about, at, into
sent to receiver of ? MESSAGE USER , Relationship received by receiver of
Optional Relationship Must every MESSAGE be sent by a USER? No Must every USER be sender of an MESSAGE? No Must every MESSAGE be sent to a USER? No Must every USER be addressed in a MESSAGE? No Yes Relationship mandatory Optional Relationship mandatory ElectronicMail MESSAGE User MESSAGE User User Relationship User System User Relationship mandatory Relationship Model optional
Degree Relationship Can a MESSAGE be written by more than one USER? No Can a USER be author of more than one MESSAGE? Yes No Degree 1 Yes Degree Many or m Relationship mandatory many Relationship A B mandatory A B A B
Optional many relationship , Email USER ,1 Message degree Message ATTACHMENTS Business ATTACHMENTS MESSAGE 4 Degree