rowspan

<style>
  tr.style15 th {border:solid 1px #000000;background-color:#66CCCC}
  tr.style8 td {border:solid 1px #000000;}
  .center {text-align:center}
</style>
<table width="766" border="1" cellspacing="1" cellpadding="1">
  <thead>
    <tr class="style15">
      <th width="25">No</th>
      <th width="50">Hari </th>
      <th>Jam</th>
      <th width="302">Matakuliah</th>
      <th width="30">SKS</th>
      <th width="130">Dosen Pengajar</th>
      <th width="150">Ruang</th>
    </tr>
  </thead>
  <tbody>
<?php
    include "koneksi.php";
    $semester = $_GET['semester'];
    $sql="SELECT
            a.hari,
            b.namadosen,
            c.jammengajar,
            d.namamk,
            d.sks,
            e.namaruang
          FROM
            tbljadwal a
            JOIN tbldosen b USING(kodedosen)
            JOIN tblwaktu c USING(koderuang)
            JOIN tblmatakuliah d USING(kodemk)
            JOIN tblruang e USING(koderuang)
          WHERE
            a.tingkatsemester = '".$_GET['angka']."'";
    $result = mysql_query($sql);
    $records=array();
    while($r=mysql_fetch_array($result))
    {
      if(isset($records[$r['hari']]))
      {
        $records[$r['hari']]=array();
        $records[$r['hari']]['num']=1;
        $records[$r['hari']]['data']=array();
        $records[$r['hari']]['data'][]=$r;
      }
      else
      {
        $records[$r['hari']]['data'][]=$r;
        $records[$r['hari']]['num']++;
      }
    }
    $no=0;
    foreach($records as $record)
    {
      $jml=0;
      foreach($record['data'] as $row)
      {
      echo "
      <tr class='style8'>
        <td>".++$no."</td>"
       .(++$jml==1?($record['num']==1?"<td>".$row['hari']."</td>":"<td rowspan='".$record['num'].">".$row['hari']."</td>"):"")
       ."<td>".$row['jammengajar']."</td>
        <td>".$row['namamk']."</td>
        <td class='center'>".$row['sks']."</td>
        <td class='center'>".$row['namadosen']."</td>
        <td class='center'>".$row['namaruangan']."</td>
      </tr>
      ";
      }
    }
    ?>
  </tbody>
</table>