将user_id置于注册状态

Question

我正在尝试将user_id插入到我的accounts_table中。但我试图在注册时从user_table获取user_ID。

我无法获取user_table中最后一个注册用户的user_id（我的accounts_table的外键），这是我需要在accounts_table上插入的内容。

但是当我var_dump（$ userData）时，我得到null值。它说 mysql_fetch_array（）期望参数1是资源，给定布尔值 为什么呢？

 $registerQuery = 'INSERT INTO   `user`(`firstname`,`lastname`,`email_address`,`password`,`mobile_number`,`address`,`birthdate`) VALUES (
    "'.ucfirst($firstname).'",
    "'.$lastname.'",
    "'.$emailaddress.'",
    "'.$password.'",
    "'.$mobile_number.'",
    "'.$address.'",
    "'.$birthdate.'"
    );';

    $qry = mysql_query($registerQuery); //INSERT TO DATABASE
    //echo $getuserIDQuery = 'SELECT `user_id` FROM `users` WHERE `email_address` LIKE \'%'.$emailaddress.'%\'';;
    echo $getuserIDQuery ="SELECT * FROM `users` WHERE `email_address` = '$emailaddress'";
    $getuserIDResult = mysql_query($getuserIDQuery);
    $userData = mysql_fetch_array($getuserIDResult) ;

    echo ' </br> ';
    var_dump($userData);
    echo ' </br> ';
    var_dump($emailaddress);
    echo '</br> ';
    echo $userData['user_id'];
    echo $emailaddress; //validation purpose only
    echo ' AND COUNT ='.count($getuserIDResult);     //check if found something 


    $accountQuery = 'INSERT INTO `accounts`(`user_id`,`balance`) VALUES (
    "'.$getuserIDResult.'",
    "'.$default_amount.'"
    );';

    $accountQry = mysql_query($getuserIDQuery);
}