从表视图和sql中删除数据

Question

I want to delete the data from table view and from SQL,after i tried almost everything i don't know where the problem is?

public void DeleteButton(ActionEvent event) throws SQLException, 
    ClassNotFoundException{

   String sql = "Delete from Add_NewOrder where No=?";
   try{
       pst = con.prepareStatement(sql);
       pst.setString(1, comboBoxTable.getValue());
       int i = pst.executeUpdate();
       if(i==1){
            Alert alert = new Alert(AlertType.ERROR);
            alert.setTitle("Information Dialog");
            alert.setHeaderText(null);
            alert.setContentText("Te dhenat nuk jane shlyer!");
            alert.showAndWait();
            loadDataFromDataBase();
            clearTextField();
       }
   }catch(SQLException ex){
        Logger.getLogger(AddNewOrderController.class.getName()).log(Level.SEVERE,null,ex);
   }
}

Answer 1

Which part isn't working?

I see lots of problems with your code:

1. Connection and PreparedStatement appear to be class variables. I'd keep PreparedStatement in method scope and close it in a finally block.
2. Method is doing two things: database and Swing UI change. Separate them into individual classes and methods. Test them separately and combine them when both are working.
3. Mixing UI and processing code in the same class is something I try to avoid. I'd partition them into separate classes.