Pasar Valor de Columna MySQL a Variable

[xerifandtomas]

$link= mysql_connect("localhost", "root", "root*") or die(mysql_error());
mysql_select_db(contencion) or die(mysql_error());
$datos=mysql_query("SELECT * FROM tabla WHERE campo1='$variable', $link);
while($row = mysql_fetch_array($datos)){
$variable2=$row['campo2'];
echo $variable2;

echo $row ['campo2'];
}



que errrores te da???