The Cast() Function is used to change the data type of a column. We can use the cast() function for various purpose.
Cast(Original_Expression as Desired_DataType)
We can use this function for the following purpose:
1. To concatenate string
2.. Joining two columns
3. Performing Unions of Table
4. Performing mathematical operation on columns
Example: For example we have an employee Table.
Select Name, WorkingHours = Cast(WorkingHours as char(2)) + 'hours working a day'