php - MySQL - 在插入时返回生成的 AUTO_INCREMENT 值

Question

希望是一个简单的解决方案 - 我想不出一个可靠的解决方案。

我正在构建一个生成 id_cart AUTO_INCREMENT 主键的购物车机制。购物车项目有另一个表，其中包含购物车产品变量，如尺寸。我想在尺码表中归因于相同的 id_cart。

CREATE TABLE
-> id_size_cart NOT NULL PRIMARY KEY AUTO_INCREMENT,
-> id_cart //THIS WILL BE THE AI value from the product cart
-> size_name

我见过 SELECT LAST_INSERT_ID()。

确保它是最后插入的 ID 有多稳固？不想让顾客买错尺码!

__ 编辑 ___

感谢您的输入。尽管如此，我还是遇到了麻烦。请参阅下面的实际代码；

//add product to cart table
$addtocart_sql = "INSERT INTO store_cart (id_cart, id_session) VALUES ('', '".$_COOKIE["PHPSESSID"]."')";
$addtocart_res = mysqli_query($dbConnect, $addtocart_sql) or die(mysqli_error($dbConnect));

$last_row_id = mysqli_query($dbConnect, "SELECT LAST_INSERT_ID()") or die(mysqli_error($dbConnect));

echo 'INSERT worked!<br/>';
echo $last_row_id;

错误显示为

Parse error: syntax error, unexpected T_STRING in /websites/LinuxPackage05/4v/35/xy/4v35xy-55415.webfusion-hosting.co.uk/public_html/noff-group.com/dev/add_to_cart.php on line 27

提前致谢。

Answer 1

来自 the manual :

For LAST_INSERT_ID(), the most recently generated ID is maintained in the server on a per-connection basis. It is not changed by another client. It is not even changed if you update another AUTO_INCREMENT column with a nonmagic value (that is, a value that is not NULL and not 0). Using LAST_INSERT_ID() and AUTO_INCREMENT columns simultaneously from multiple clients is perfectly valid. Each client will receive the last inserted ID for the last statement that client executed.