pdo调用mysql存储过程-PHP源码

$stmt = $dbh->prepare("CALL test(:bb)");
$aa = '';
$stmt->bindParam(':bb', $aa, PDO::PARAM_STR|PDO::PARAM_INPUT_OUTPUT, 4000);
var_dump($stmt->execute());
var_dump($aa);
var_dump($stmt->fetchAll(PDO::FETCH_ASSOC));

$stmt = $dbh->prepare("select * from userinfo where u_id=:id");
$aa = 1;
$stmt->bindParam(':id', $aa, PDO::PARAM_STR|PDO::PARAM_INPUT_OUTPUT, 4000);
var_dump($stmt->execute());
var_dump($stmt->fetchAll(PDO::FETCH_ASSOC));