JS - scrolování v tabulce, aby zůstal nadpis stále vidět

<table>
  <tr>
    <td>
    ID
    </td>
    <td>
      Číslo řádku
    </td>
    
  </tr>


<?php


                $i = "0";
                for ($i=0 ; $i<$denik_num ; $i++){
                
  $id = MySQL_Result($denik, $i,"id");
  $cis_radku = MySQL_Result($denik, $i,"cis_radku");
  
  
  ?> 
  <tr>
  
    <td><input type="text" id="id" value="<?php echo $id;?>" name="id[]" size="10" onMouseDown="return zvyrazni_radek(this)" onkeypress="return tabE(this,event)"></td>
    <td><input type="text" id="cis_radku" value="<?php echo $cis_radku;?>" name="cis_radku[]" size="10" onkeypress="return tabE(this,event)"></td>