how to prepaare a mysql request pdo code example

Example: preared request pdo

<?php
/* Exécute une requête préparée en passant un tableau de valeurs */
$sql = 'SELECT nom, couleur, calories
    FROM fruit
WHERE calories < :calories AND couleur = :couleur';
$sth = $dbh->prepare($sql, array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY));
$sth->execute(array(':calories' => 150, ':couleur' => 'red'));
$red = $sth->fetchAll();
$sth->execute(array(':calories' => 175, ':couleur' => 'yellow'));
$yellow = $sth->fetchAll();
?>