I have to fill a combox with a single data from the database and I can not do it please someone to help me thanks 
this is the image of my database this is the code I am using 
and I need to show it in this part where it says search by date 
I will thank you a thousand thanks, this is to finalize my thesis and I am a beginner in this language, all in MYSQL
I hope you will use my bro code!
import javax.swing.*;
import java.sql.*;
class LlenaCombo extends JFrame{
private JComboBox miCombo;
private Connection conexion;
private Statement sentencia;
private ResultSet resultado;
private String sql;
public LlenaCombo(){
conexion = DriverManager.getConnection(AQUI PONES TU RUTA);
sql = "SELECT DISTINCTROW DATO FROM TU BD";
sentencia = conexion.createStatement(sql);
resultado = sentencia.executeQuery();
miCombo = new JComboBox("DATO");
while(resultado.next()){
miCombo.addItem(resultado.getString(1));
}
}
}
Important:
Distinctrow: adds a single column in specific == > the data in that column.
In the loop: the combobox is filled every loop loop with each row of the column.
// About the class
DefaultComboBoxModel modelCombo = new DefaultComboBoxModel (); // I create the model to load items DefaultComboBoxModel modelCombo2 = new DefaultComboBoxModel (); // I create the model to load items
// In the constructor
jComboBox5.removeAllItems (); // Delete current items jComboBox1.removeAllItems (); // Delete current items fill_combo (1); // Fill the group combo fill_combo (2);
// The method
public void fill_combo (int selec) { String informationTable=""; String informacionCampo="";
switch(selec){
case 1:
informacionTabla = "tabla_grupo";
informacionCampo = "nombre_encargado";
break;
case 2:
informacionTabla = "tabla_trabajo";
informacionCampo = "nombre_trabajo";
default:
System.out.println("No existe opcion para el llenado del combo.");
break;
}
try {
lb = new LibreriaHerramientas();
String Sql = "SELECT "+ informacionCampo + " as Name "
+ " FROM "
+ informacionTabla; // Escribo la sentencia !!
PreparedStatement us = lb.conex().prepareStatement(Sql); //
ResultSet res = us.executeQuery(); //
if(selec == 1){
modeloCombo.addElement("Seleccione un Campo");//es el primer registro q mostrara el combo
jComboBox5.setModel(modeloCombo);//con esto lo agregamos al objeto al jcombobox
}
if(selec == 2){
modeloCombo2.addElement("Seleccione un Campo");//es el primer registro q mostrara el combo
jComboBox1.setModel(modeloCombo2);//con esto lo agregamos al objeto al jcombobox
}
while (res.next()) {
//jComboBox5.setModel(modeloCombo);
if(selec == 1){
modeloCombo.addElement(res.getObject("Name"));
jComboBox5.setModel(modeloCombo);//con esto lo agregamos al objeto al jcombobox
}
if(selec == 2){
modeloCombo2.addElement(res.getObject("Name"));
jComboBox1.setModel(modeloCombo2);//con esto lo agregamos al objeto al jcombobox
}
}
res.close();
} catch(SQLException ex){
}
}