Normal-Forms
Question 1 |
An instance of a relational scheme R(A, B, C) has distinct values for attribute A.
Can you conclude that A is a candidate key for R?
Yes | |
No |
Question 1 Explanation:
Because FD's are defined on the schema itself, not the instance. So, based on the state of the instance we cannot say what holds for schema (there can be many instances for R).
Question 2 |
A relation Empdtl is defined with attributes empcode (unique), name, street, city, state and pincode. For any pincode, there is only one city and state. Also, for any given street, city and state, there is just one pincode. In normalization terms, Empdtl is a relation in
1NF only | |
2NF and hence also in 1NF | |
3NF and hence also in 2NF and 1NF | |
BCNF and hence also in 3NF, 2NF an 1NF |
Question 2 Explanation:
It is in 2NF. For 2NF all non-prime attribute should be fully functionally dependent on key.
Here key is empcode and contains only one attribute, hence no partial dependency. But there is transitive dependency in this.
Pincode → city, state, so it is not in 3NF.
Here key is empcode and contains only one attribute, hence no partial dependency. But there is transitive dependency in this.
Pincode → city, state, so it is not in 3NF.
There are 2 questions to complete.