PHP & MySQL: The ORDER BY Keyword

The ORDER BY keyword is used to sort the data in a recordset.

The ORDER BY keyword sort the records in ascending order by default.

If you want to sort the records in a descending order, you can use the DESC keyword.
Syntax:
SELECT column_name(s)
FROM table_name
ORDER BY column_name(s) ASC|DESC

The following example selects all the data stored in the "Persons" table, and sorts the result by the "Age" column:

$con = mysql_connect("localhost","peter","abc123");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}

mysql_select_db("my_db", $con);

$result = mysql_query("SELECT * FROM Persons ORDER BY age");

while($row = mysql_fetch_array($result))
{
echo $row['FirstName'];
echo " " . $row['LastName'];
echo " " . $row['Age'];
echo "
";
}

mysql_close($con);
?>

The output of the code above will be:
Glenn Quagmire 33
Peter Griffin 35


Order by Two Columns
It is also possible to order by more than one column. When ordering by more than one column, the second column is only used if the values in the first column are equal:

SELECT column_name(s)
FROM table_name
ORDER BY column1, column2