Unlock the secrets of Candidate Keys in DBMS! Discover how they ensure database integrity & boost your data management skills. Read now!
Let's look at the same example took while discussing Super Key to understand the working of a candidate key. We have anEMPLOYEE_DETAILtable where we have the following attributes: Emp_SSN:The SSN number is stored in this field. Emp_Id:An attribute that stores the value of the employee id...
Example 1:Give R(X, Y, Z, W) and Set of Functional Dependency FD = { X → Y, Y → Z, Z → X}. The question is to calculate the candidate key and no. of candidate key in above relation R using a given set of FDs. Let us construct an arrow diagram on R using FD From th...
If the database engineer attaches a candidate key to the table composed of arbitrary alphanumerical input, that candidate key will do the same thing that the time and terminal super key attribute combination does, with just one column. With all of this in mind, the use of a candidate key c...
One of the candidate keys is chosen as primary key byDBA. Provided, that the key attribute values must be unique and does not contain NULL. The attributes of Candidate key is calledprime attributes. In above example, we have found the Super keys for relation R. Now, let us check all th...
Example:In the above example, we had 6 super keys but all of them cannot become a candidate key. Only those super keys would become a candidate key which have no redundant attributes. {Roll_no}:This key doesn't have any redundant or repeating attribute. So, it can be considered as a ...