php pdo bindvalue array
<?php
$ids     = array(1, 2, 3, 7, 8, 9);
$inQuery = implode(',', array_fill(0, count($ids), '?'));
$db = new PDO(...);
$stmt = $db->prepare(
    'SELECT *
     FROM table
     WHERE id IN(' . $inQuery . ')'
);
// bindvalue is 1-indexed, so $k+1
foreach ($ids as $k => $id)
    $stmt->bindValue(($k+1), $id);
$stmt->execute();
?>