The table below is an attribute table about employee records. Which attribute can be used as a primary key?
Employee Name Designation Department (Emp_ID) (Emp_Name) (Emp_Desig) (Emp_Dept) 100260 Prashant Software Developer Information Technology 100265 Dinesh Junior Engineer Embedded System 100252 Somya HR Manager Management 100271 Dinesh Junior Engineer Information Technology
The table below is an attribute table about employee records. Which attribute can be used as a primary key?
| Employee | Name | Designation | Department |
|---|---|---|---|
| (Emp_ID) | (Emp_Name) | (Emp_Desig) | (Emp_Dept) |
| 100260 | Prashant | Software Developer | Information Technology |
| 100265 | Dinesh | Junior Engineer | Embedded System |
| 100252 | Somya | HR Manager | Management |
| 100271 | Dinesh | Junior Engineer | Information Technology |
Show Hint
- \( {Emp\_Name} \)
- \( {Emp\_ID} \)
- \( {Emp\_Dept} \)
- \( {Emp\_Desig} \)
The Correct Option is B
Solution and Explanation
Emp_Name is not unique (e.g., "Dinesh" appears twice),
Emp_Desig and Emp_Dept are also repeated for different employees,
Emp_ID, however, is unique for each row, making it the only suitable attribute to be a primary key.
Hence, the correct answer is Emp_ID.
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