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Introduction to Database Systems

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• What is Data
  • Data is any known fact that can be recorded and that have explicit meaning
    • Names
    • Phone numbers
    • ...

• Tools to record data electronically
  • editors
  • spreadsheet (Excel)
  • database systems

• What is a Database
  • a logically coherent collection of data
  • is built for a special purpose - intended for a specific group(s) of users with some pre-conceived set of applications
  • represents only some aspect of the real world (but not every aspect)
  • the "reality" represented by a database is called a "mini world"

• Example Databases
  • telephone book
  • library catalog
  • hotel registration