I have 3 joined tables. The main one (User) contains the fields: user_id, 
fname, sname, dept_id, location_id, extension. The second one (Department) 
contains dept_id and department. The third (Location) contains location_id 
and area.
In order to add a new user to the User table, I have created a form that 
contains two dropdown lists that are populated by the departments and the 
areas from their respective tables, along with text boxes to input fname, 
sname and extension.
How do I write the statement to add the dept_id and location_id along with 
the other fields into the User table when the form is submitted?