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Summary: March 23, 2008 DB:Relational Calculus 1
Relational Calculus
March 23, 2008 DB:Relational Calculus 2
Objectives
Introduction +
Tuple Relational Calculus +
Domain relational Calculus +
QBE +
March 23, 2008 DB:Relational Calculus 3
- Introduction
Relational calculus is a formal query language where
we write one declarative expression to specify a
retrieval request.
A calculus expression specifies what is to be retrieved
rather than how to retrieve it. Therefore, relational
calculus is considered to be a nonprocedural
language.
There are two types of relational calculus:
Tuple relational calculus
Domain relational calculus.
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