Database - The Relational Model and Normalization - Discussion
Discussion Forum : The Relational Model and Normalization - True or False (Q.No. 21)
21.
A primary key is a composite key that was selected to be the main identifier for the relation.
Discussion:
7 comments Page 1 of 1.
Ruchi Gupta said:
1 decade ago
Primary key is minimal candidate key that is define at the time of creating a table.
Rajesh raikwar said:
1 decade ago
Primary key is one of the candidate key.
Nabarun said:
1 decade ago
Is the primary key main identifier of relation ?
Nitesh said:
1 decade ago
Primary key is a minimal of candidate key. As we know every candidate key is also composite key. And primary key is also candidate key. The only difference is, it is used by Database Administrator for uniquely identify any row (Tuple) from table.
Hem tiwari said:
1 decade ago
A primary key identify a row, like registration number or id.
Lehlohonolo said:
1 decade ago
A primary key is a candidate key that is selected to uniquely identify a row in a relation.
Lehlohonolo said:
1 decade ago
It can be composite, depending on the functional dependency of the attributes in the table or relation.
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