PHP - Borrar Registros

borra.php
<table>
<tr>
<td><B>ID</B></td>
<td><B>Descripcion</B></td>
<td><B>Borrar</B></td>
</tr>
<?php
$cstr="Driver=iSeries Access ODBC Driver;UID=FLOPEZLL;pwd=LOPEZ1;SIGNON=1;".
"PKG=ISOPRO/DEFAULT(IBM),2,0,1,0,512;LANGUAGEID=ENU;DFTPKGLIB=ISOPRO;DBQ=ISOPRO;SYSTEM=HACSA";
$conn=odbc_connect($cstr,'FLOPEZLL','LOPEZ1');
$query=("select * from empresas");
$resultset=odbc_exec($conn, $query);
while ($row = odbc_fetch_array($resultset)){
printf ("
<tr>
<td></td>
<td></td>
<td><a href=\"borrar.php?id=%d\">Borrar</a></td>
</tr>", $row["emp_id"],$row["emp_desc"]);}
?>
</table>

borrar.php
<?php
include("conex.php");
$id=$_POST['emp_id'];
$query="delete from empresas where emp_id = $id";
header("Location: borra.php");
?>