ENCAPSULATION

1. DBMS SUPPLIES SYSTEM DEFINED OPERATIONS TO READ AND MODIFY ATTRIBUTES - APPLICATIONS CAN OVERRIDE DEFINITION
   
   
   • RESULTS IN AN EFFICIENT (LOW LEVEL) IMPLEMENTATION & AVOIDS APPLICATION NEED TO DEVELOP A NUMBER OF METHODS FOR ATTRIBUTE ACCESS
   
   
2. DBMS ALLOWS APPLICATION TO DECLARE CERTAIN ATTRIBUTES & METHODS PUBLIC & PART OF THE OBJECT INTERFACE - SIMILAR TO C++ APPROACH

3. DBMS ALLOWS READ/WRITE ACCESS TO ALL ATTRIBUTES & ALL METHODS CAN BE INVOKED I.E. EVERYTHING IS PUBLIC & PART OF THE OBJECT INTERFACE
   
   
   • AUTHORIZATION MECHANISMS CAN LIMIT SUCH ACCESS
   
   
   

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   Ugo O. Gagliardi
   GSD-6306 Spring 2003-2004