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| Edgar F. Codd |
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| Relational
Algebra/Calculus |
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| • | Developed from
1971-1974 |
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| • | Relational
Algebra - a procedural |
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| language: |
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| – | Relations |
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| – | Relational
operators |
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| • | Relational
Calculus - a declarative |
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| language with
equivalent power. |
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