2 identical elements returned in array, after mysql query, why?

Question

Ive made a mysql query using PDO like this

$timestamp_query = "SELECT timestamp FROM change_me;";

foreach ($conn->query($timestamp_query) as $times ) {
    print_r($times); 
    echo "<br>";
 }

But this is giving me back a set of arrays like this

Array ( [timestamp] => 2013-05-24 17:55:04 [0] => 2013-05-24 17:55:04 )
Array ( [timestamp] => 2013-05-24 18:00:05 [0] => 2013-05-24 18:00:05 )
Array ( [timestamp] => 2013-05-24 18:05:04 [0] => 2013-05-24 18:05:04 ) 

Why is this giving me 2 identical elements in each array, as opposed to just one ?

Answer 1

It returns an associative array to you so you can reference the results by either field name or index.

E.g. $times['timestamp'] or $times[0]