Declarative Rule

• Name: Relational Algebra Selection
• Description in English: This rule represents the relational algebra selection operator. It filters an input relation according to a selection expression, producing another relation.
• Example in English: Select("r(x, y)", "x = 7", "s(x, y)") Select("r(x, y)", "x > y ^ y <= 3", "s(x, y)")
• Source(s):
  • Name: A Relational Model of Data for Large Shared Data Banks
  • URL: http://www.acm.org/classics/nov95/
  • Author(s):
    • Name: Edgar F. Codd
    • URL: http://www.acm.org/awards/turing_citations/codd.html
  • Publisher:
    • Name: Association for Computing Machinery
    • URL: http://www.acm.org/
  • Year: 1970

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