What is the difference between Select and Project Operations

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深忆病人
深忆病人 2020-12-23 20:42

I\'m referring to the basic relational algebra operators here.
As I see it, everything that can be done with project can be done with select.

I don\'t know if

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  •  一向
    一向 (楼主)
    2020-12-23 21:15

    Select Operation : This operation is used to select rows from a table (relation) that specifies a given logic, which is called as a predicate. The predicate is a user defined condition to select rows of user's choice.

    Project Operation : If the user is interested in selecting the values of a few attributes, rather than selection all attributes of the Table (Relation), then one should go for PROJECT Operation.

    See more : Relational Algebra and its operations

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