PHP INSERT 查询不适用于 web 服务器，但适用于 localhost。 没有返回错误

Question

I am fairly new to php and mysql to feel free to suggest any improvements to my code.

Recently I finished a project which works completely fine on my localhost XAMPP server, which is why I decided to then upload it to a web server to make it public. Now the problem is that all my INSERT queries stop working while they are on the web server. They seem to work fine on the offline XAMPP on localhost. While the insert queries don't work, there are no errors returned so I'm really frustrated at this point.

Any help on this would be greatly appreciated. Below is the code I have used for the insert queries.

$firstname = $_POST['firstname'];
$job_role  = $_POST['job_role'];
$password  = $_POST['password'];
$username  = $_POST['username'];

$conn = mysqli_connect("localhost", "root", "password", "id11597687_inventory");

mysqli_query($conn, "INSERT into users (`id`, `username`, `password`, `access_level`, `name` ) VALUES('', '$username', '$password', '$job_role', '$firstname')");

Answer 1

Delete 'id' from (...columns) and '' from (...values) .

It should looks like

mysqli_query($conn, "INSERT into users (`username`, `password`, `access_level`, `name` ) 
VALUES('$username', '$password', '$job_role', '$firstname')");

Auto incrementation makes +1 to the new value of defined column, in your case it's id .

Also, take care of SQL injection

Answer 2

1. Considering that you are using the values posted from an HTML form, you would like to use something like below -

    $var= mysqli_real_escape_string ($con,$_POST['var']);

2. Assuming that the 'id' field is an auto-increment value - use something like -

    $sql = "INSERT INTO users (id, username,password, access_level,name) VALUES (NULL,'$_POST[username]','$_POST[password]','$_POST[access_level]','$_POST[name]')"; mysqli_query($conn,$sql)