Create a trigger named InstructorInsertSalaryTR that fires when a new row is added to the Instructors table.
Throw an error when multiple rows are inserted.
When there is only one row inserted, validate that the AnnualSalary value is positive (strictly greater than zero) and less than or equal to 120000. Throw an error with appropriate message if the salary value is negative or too big.
Also, if the salary value is between 0 and 10000, assume that there was a mistake of entering monthly salary instead of annual salary, and multiply the salary value by 12. For example, if the new value of the salary is 5000, it should be changed to 60000.
No need to validate any other data from the inserted row.
Test the trigger with appropriate INSERT statements. There should be four cases: 1) with negative salary, 2) with positive salary <= 10000,="" 3)="" with="" salary="" greater="" that="" 10000="" and="" less="" than="" or="" equal="" to="" 120000,="" and="" 4)="" with="" salary=""> 120000.