format de date php jj / mm / aaaa
date("d/m/Y", strtotime($str));
php convertit la date de jj/mm / aaaa en aaaa-mm-jj
$date = DateTime::createFromFormat('d/m/Y', "24/04/2012");
echo $date->format('Y-m-d');
php change le format de date de j/m / a en y-m-d
$var = '20/04/2012';
$date = str_replace('/', '-', $var);
echo date('Y-m-d', strtotime($date));
convertir jj / mm / aaaa en aaaa-mm - jj en php mysql
$var = '20/04/2012';
$date = str_replace('/', '-', $var);
echo date('Y-m-d', strtotime($date));