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Which operation is used to extract specified columns from a table?

  1. Project
  2. Join
  3. Extract
  4. Substitute
in Databases by | 1.7k views

6 Answers

+18 votes
Best answer

To extract a specified row in a table we do select operation

To extract a specified column from a table we do project operation

Answer A)

by
selected by
+2 votes

Answer is Project

To choose a subset of columns in a relation Project operation is used

It is denoted as Π.

by
+1 vote
project
by
+1 vote

project

by
+1 vote
project is use to extract specified columns from a table it also eliminate dublicate .
by
0 votes
Project for column

And select for row

Option a is correct
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