如何使用PHP同时插入主键和外键值

Question

我有两张桌子

1. user_details
2. load_owner

user_details

user_id as primary key

name

password

phone

load_owner

load_owner_id as a primary key

user_id as foreign key

address

bank name

我需要同时插入所有值。我尝试了但是在load_owner表中user_id值是插入为NULL。我的PHP代码如下：

if(isset($_POST['submit']))
 {
     $name = $_POST['name'];
     $phone = $_POST['phone'];
     $password = $_POST['password'];
     $address = $_POST['address'];
     $bank_name = $_POST['bank_name'];


     $user_insert = mysql_query("insert into user_details (name, password, phone) values ('$name', '$password', '$phone')");
     if($user_insert==false)
     {
         echo "".mysql_error();
     }
     $load_owner_insert = mysql_query("insert into load_owner ( address, bank_name) values ('$address''$bank_name')");
     if($load_owner_insert==false)
     {
         echo "".mysql_error();
     }
 }
 ?>   

Answer 1

这是因为在插入load_owner表时实际上并没有指定user_id值。您需要首先获取user_id值，以便它变为：

 $user_insert = mysql_query("insert into user_details (name, password, phone) values ('$name', '$password', '$phone')");
 $user_id = mysql_insert_id();

然后将user_id插入load_owner

 $load_owner_insert = mysql_query("insert into load_owner ( user_id, address, bank_name) values ($user_id, '$address', '$bank_name')");

PS：使用带有预准备语句的 PDO ，此SQL查询容易出现SQL Injections，并且不推荐使用mysql库。