Querying a database and populating a combobox

[Splatify]

Ok so now i have this:

ui->QuizBox->setModel(model);
    ui->QuizBox->setModelColumn(1);

ui->QuizBox->setModel(model);
    ui->QuizBox->setModelColumn(1);

To copy to clipboard, switch view to plain text mode 

I'm still unsure of how to use this model. Could you give me some example code of how to use the model when an item is selected in the combobox and a button is pressed.

Thanks very much