Вывод записей из нескольких таблиц в comboBox

using System;
using System.Data;
using System.Windows.Forms;
 
namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
            Database1DataSetTableAdapters.TableTableAdapter Table_TA = new Database1DataSetTableAdapters.TableTableAdapter();
            Database1DataSet.TableDataTable BD_DT = new Database1DataSet.TableDataTable();
            Table_TA.FillBy(BD_DT);
 
            DataTable DT = new DataTable("Full_ID");
            DataColumn nameColumn = new DataColumn("ID", Type.GetType("System.String"));
            DT.Columns.Add(nameColumn);
 
            string full_name;
            foreach (DataRow row in BD_DT)
            {
 
                full_name = (string)row["Name"] + (string)row["SurName"] + "-" + (int)row["Code"] + (string)row["Town"];
                DT.Rows.Add(new object[] { full_name });
            }
 
            comboBox1.DataSource = DT;
            comboBox1.DisplayMember = "ID";
            comboBox1.ValueMember = "ID";
        }
    }
}