Database PDO SQL 状态00000但仍然错误

有人能解释为什么吗

$sql->execute($params);

返回FALSE，而

print $pdo->errorCode();
print_r($pdo->errorInfo());

两者都返回SQLSTATE 00000，这意味着根据文档显示成功了吗？它是INSERT，实际上没有向数据库中插入任何内容.那么，为什么我会收到来自SQLSTATE的成功消息呢？

如果有帮助，这是代码...

$sql = $pdo->prepare("
        INSERT INTO user (
            username, fname, pass, salt, email,
            loc_id_home, country_id_home, region_id_home,
            cont_id_home, timestamp_reg, timestamp_upd, timestamp_lastonline, 
            online_status, gender, birthdate
            )
        VALUES (
            :username,:fname,:pass,:random_salt,:email,
            :loc_id_home,:country_id_home,:region_id_home,
            :cont_id_home,'".time()."','".time()."','".time()."',
            1,:gender,:birthdate)
        ");

$params=array(
    ':username'=>$username,
    ':fname'=>$fname,
    ':pass'=>$pass,
    ':random_salt'=>$random_salt,
    ':email'=>$email,
    ':loc_id_home'=>$loc_id_home,
    ':country_id_home'=>$country,
    ':region_id_home'=>$region,
    ':cont_id_home'=>$continent,
    ':gender'=>$gender,
    ':birthdate'=>$birthdate
);  

$sql->execute($params);

print $pdo->errorCode();
print_r($pdo->errorInfo());