Jak vytvořit pole JSON z databáze mysql

Je něco takového to, co chceš dělat?

$return_arr = array();

$fetch = mysql_query("SELECT * FROM table"); 

while ($row = mysql_fetch_array($fetch, MYSQL_ASSOC)) {
    $row_array['id'] = $row['id'];
    $row_array['col1'] = $row['col1'];
    $row_array['col2'] = $row['col2'];

    array_push($return_arr,$row_array);
}

echo json_encode($return_arr);

Vrací řetězec json v tomto formátu:

[{"id":"1","col1":"col1_value","col2":"col2_value"},{"id":"2","col1":"col1_value","col2":"col2_value"}]

NEBO něco takového:

$year = date('Y');
$month = date('m');

$json_array = array(

//Each array below must be pulled from database
    //1st record
    array(
    'id' => 111,
    'title' => "Event1",
    'start' => "$year-$month-10",
    'url' => "http://yahoo.com/"
),

     //2nd record
     array(
    'id' => 222,
    'title' => "Event2",
    'start' => "$year-$month-20",
    'end' => "$year-$month-22",
    'url' => "http://yahoo.com/"
)

);

echo json_encode($json_array);