PHP returns array data mysql_fetch_array() function

$conn = mysql_connect("server name", "username", "password");
mysql_select_db("database name", $conn);
$result = mysql_query("select * from table", $conn);
while($row = mysql_fetch_array($result)) {
echo $row["a_id"];
echo $row["a_name"];
}
mysql_free_result($result) ;
?>