Question: Create ERD diagrams in SmartDraw / SmartDraw equivalent that represent each anomaly instance below. Consider a relation Employee _ Department with the following attributes: EmployeeID
Create ERD diagrams in SmartDrawSmartDraw equivalent that represent each anomaly instance below.
Consider a relation EmployeeDepartment with the following attributes:
EmployeeID As a primary key in this relation
EmpName
EmpAddress
DepartmentID
DeptName
DeptManager
In the above relation, the different type of anomaly occurs in the following situation:
Insertion anomaly:
Suppose a new department has been started by the organization. In starting there exists no employee appointed for that department, then the tuple for this new department cannot be inserted into this EmployeeDepartment table as EmployeeID will have NULL, which is not allowed as EmployeeID is primary key.
So in this case, Insertion anomaly will be occurred.
Deletion anomaly:
Suppose that there exists only one employee in some department and then employee left the organization. In this case, the tuple of that employee has to be removed from the table and also the information about the department also will get deleted.
So in this case, Deletion anomaly will be occurred.
Modification anomaly:
Suppose, in the provided relational schema, the department manager has been changed. This corresponds that DeptManager in every tuples corresponding to that department must be replaced to reflect the current status.
If user fails to update every tuples of the given department, then in this case two different records of employee working in the same department might display different DeptManager. This will cause a database inconsistency.
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