BASIC NOTIONS

• THE NOTIONS INCORPORATED IN THE CORE MODEL ARE:
  
  
  • OBJECTS & IDs: EACH REAL WORLD ENTITY (IN THE ER SENSE) IS MODELED AS AN OBJECT

  • COMPLEX OBJECTS: A SET OF ATTRIBUTES IS ASSOCIATED TO EACH OBJECT - THE VALUE OF AN ATTRIBUTE CAN BE AN OBJECT OR A SET OF OBJECTS

  • ENCAPSULATION: EACH OBJECT CONTAINS & DEFINES:
    
    
    • PROCEDURES (METHODS)
    • INTERFACE (OPERATIONS) THROUGH WHICH IT CAN BE ACCESSED BY OTHER OBJECTS
    • STATE (VALUE OF ATTRIBUTES) MANIPULATED BY METHODS INVOKED BY CORRESPONDING OPERATIONS
    
    
  
  

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Ugo O. Gagliardi
GSD-6306 Spring 2003-2004