Lecture 7

Announcements
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- Hw#2 is up, due on thursday
- Hw#1 answers are posted, let me know if you find any mistakes
- Lecture exercise after class

ER Data Modeling Paradigm
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-- Object-oriented data modeling:

   entity-relationship data models

-- Entity: basic object classes that we will store data about
   Define: name of entity
           its key
	   a number of attributes

-- Relationships: information that connects two or more entities


Student
   RIN: Key
   Name
   Email
   Address
   Class
   GPA


- Converting an ER diagram to relational data model


  - Convert each entity into a relation
    Attributes of the entity become attributes of the relation
    KEy of the entity becomes key of the relation

  - For binary relationships: 

    If it is one-to-many: take the key for the entity on the 1 side
    and include it as an attribute in the other entity.

    If it is one-to-one: then you can include the key of one entity
    in the other relation

    If it is many-to-many: then create a new relation that has the
    key of each entity it combines, the combination of the keys will
    be the key of the new relation.

    Any attribute that the relationship has goes to the entity that it
    is mapped to.













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ER Diagrams
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Covid-19/Health informatics/Health and Fitness
Financial data/transactions
Sports
Politics
Animals
Spotify


IMDB
Jeopardy
Olympics
Radio/Spotify
Movies/Streaming 
Yelp
AirBnB


Movie DB
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Movies
    id: primary key
    duration
    release date
    title
    US_Rating
    BoxOfficeWinnings

Actors
    id: key
    name
    stage name
    dob
    place of birth
    dod
    biopgraphy
    education

Studios
    name: key
    country of origin
    
Directors:
    id: key
    name
    stage name
    dob
    place of birth
    dod
    biopgraphy
    education
   
Awards
    name  //oscars
    type  //best picture
    frequency
    first_year_given
    key: name, type