How to update table information in sqllite at location specified in JComboBox?

I have created an interface, in which the user selects one of the pre-specfied employee ID's and enters a series of data(hours worked) to be processed and inserted into an sqllite table at the specified EmployeeID location. My question is how to I update the table at a location when it is specified in a JComboBox? Below I have posted an example of what is stopping me. RegHRs, and OT_Hrs are both location specified in my sqllite Table.

String sql = "Insert into EmployeeInfo (RegHRs,OT_HRs) values(?,?) where EmployeeID = '"+JComboBox.getSelectedItem()+"'";