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1.2.06. Select operation

  • SELECT a subset of tuples from a relation
    • Uses selection condition
      • Evaluate each tuple to true of false
      • False tuples discarded
    • Sigma (s)
    • output = s(cond)(input_relation)
    • Relation schema: R(output) = R(input_relation)
    • Commutative
    ‹ 1.2.05. Basic algebraup1.2.07. Project operation ›
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