updated: 2022-01-23_12:32:31-05:00

Select

  • select tuples that satisfy a given predicate

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  • where P is called the Selection Predicate

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  • Allows comparisons using:

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  • Combination operators:

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  • Comparisons between two attributes

    • EG: find all departments whose name is the same as their building name:
      • dept_name = building (department)
        • Quotations is literal, without them, it's getting the value stored in that attribute