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The PROJECT operation
The project operation is used to choose the records with specified attributes as discarding the others based on some related criteria. This is denotes as ∏
(Relation) Example:
Consider the relation PERSON. If you want to display only the names of persons then the project operation will be used as follows:
Π Name (PERSON)
The resultant relation will be as follows:
NAME
Sanjay Prasad
Sharad Gupta
Vibhu Datt
Note: -
1) Π ( Π (R))= Π (R)
As long as have attributes in .
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