[php] mysql select replace array

$query = "select * from $j2hkeyword  order by id  ";

$result=mysql_query($query);

$number = mysql_num_rows($result);

$name = array();

$domain = array();

while ($i < $number){

$row = mysql_fetch_array($result);     

$domain[]=$row["domain"];

$name[]=$row["name"];

$i++;

}

$value = str_replace($name, $domain, $string) ;

echo $value;