Civil Engineering MCQJE Level Civil Engineering
While reviewing primary key, which conclusion is correct? Avoid the common trap that primary key must be duplicated in every row.
Computer ApplicationsDatabaseHARD
Choose the correct answer
A
a primary key uniquely identifies a record in a table
B
primary key is always null
C
primary key stores only images
D
primary key must be duplicated in every row
Correct Answer
A. a primary key uniquely identifies a record in a table
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Primary keys enforce entity identity. Correct option: A.
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This MCQ belongs to RRB JE Civil & Allied Engineering CBT-2 Full Mock Test Series. Full tests include timed attempts, rank comparison and subject-wise analysis.