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Database Management System

  • The Relational Model
  • Database design and Normalization
  • Relational Algebra
  • SQL
  • Transaction
  • Concurrency Control Techniques
  • File Organization and Indexing

The Relational Model

  • er - entity relationship model
  • database design and er diagrams
    • requirement analysis
    • conceptual database design
    • logical database design
  • entity
    • object that exists and is distinguishable form other objects
    • concrete - person, abstract - job
    • has attributes
  • entity set
    • collection of similar entities
    • need not be disjoint
    • they have same attributes
  • relationship
    • associations between two entities
    • can have descriptive attributes
  • relationship set
    • relationships of same type
    • relate two or more entity sets

relationship constraints

  • participation constraints
    • total - existence dependency
      • entity set \(E\)
      • in a relationship \(R\)
      • every entity in \(E\)
      • is at least in on relationship in \(R\)
    • partial