"No one is harder on a talented person than the person themselves" - Linda Wilkinson ; "Trust your guts and don't follow the herd" ; "Validate direction not destination" ;

February 11, 2016

Data Models

Captured Notes from Session #2 - Data Models

Hierarchical Data Models
  • Tree like structures
  • Used in Windows Registry
  • Frequent Use (IMS)
  • DL / 1 Programming language for IMS
  • Difficult to reorganize
Graph / Network Model
  • Organize collection of records in form of directed graph
  • 3 way relationships can't be maintained
ER Model
  • Defined in terms of Entity, Relationships
  • Never Caught on Physical Model
Object Oriented Database model
  • Difficult mapping programming objects to database objects
Relational Model
  • Better physical data independence
  • Better logical independence
  • Won because of linear algebra
Happy Learning!!!