Question 9796 – Digital-Logic-Design
December 11, 2023GATE 2014 [Set-3]
December 11, 2023ER-Model
|
Question 8
|
A prime attribute of a relation scheme is an attribute that appears
|
in all candidate keys of R.
|
|
|
in some candidate key of R.
|
|
|
in a foreign key of R.
|
|
|
only in the primary key of R .
|
Question 8 Explanation:
A prime attribute of a relation scheme R is an attribute that appears in some candidate keys of R. Need not to appear in all the candidate keys.
Ex: AB, BC, CD are candidate keys of R(ABCD). In the FDs set one attribute may not be part of all the FDs.
Ex: AB, BC, CD are candidate keys of R(ABCD). In the FDs set one attribute may not be part of all the FDs.
Correct Answer: B
Question 8 Explanation:
A prime attribute of a relation scheme R is an attribute that appears in some candidate keys of R. Need not to appear in all the candidate keys.
Ex: AB, BC, CD are candidate keys of R(ABCD). In the FDs set one attribute may not be part of all the FDs.
Ex: AB, BC, CD are candidate keys of R(ABCD). In the FDs set one attribute may not be part of all the FDs.