RelationalAlgebraParser/syntax.readme at master · Zwackelmann/RelationalAlgebraParser · GitHub

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Syntaxbeispiele:
    Selektion:
      σ|matNr=1234321| student
      σ|name="Bob"| student

    Projektion:
      π|att1, att2| rel

    Umbenennung:
      - Attribute umbenennen
          ρ|(newAtt1, newAtt2, newAtt3)| rel
      - Relation umbenennen
          ρ|newRel| oldRel
      - Beides umbenennen
          ρ|newRel(newAtt1, newAtt2, newAtt3)| oldRel

    Aggregation:
      |att1, att2|F|count(*)| rel
      |att1, att2|F|count(att)| rel
      F|count(*)| rel
      F|sum(att)| rel

    Join:
      rel1 [X]|pkey=fkey| rel2
      rel1 [X|pkey=fkey| rel2
      rel1 X]|pkey=fkey| rel2
      rel1 [X]|att1, att2| rel2

    Setoperatoren:
       rel1 union rel2
       rel1 intersect rel2
       rel1 except rel2