它没有在数据库中插入值

Question

I am trying to insert a value in the database but when I open up the database the value is not inserted in the table. Now all of the code is correct in terms of no misspelling or anything like that but why isn't it inserting a value in the DB table?

I just have to say that this field is not a primary key field, I am just testing this field which is a non primary key field, will it not insert a value in the db table if the primary key value is not inserted?

Below is the code:

<?php
    session_start();

    $username="xxx";
    $password="xxx";
    $database="mobile_app";

    mysql_connect('localhost',$username,$password);

    @mysql_select_db($database) or die( "Unable to select database");


    $sql="INSERT INTO Session (Course)
    VALUES
    ('$_POST[course]')";

    mysql_close();

    if (isset($_POST['course'])) {

    $_SESSION['course'] = $_POST['course'];

    }

    ?>

Answer 1

You will need to add the Primary Key in there. You can't add a row to the database without specifying the Primary Key, unless the Primary Key is auto-generated (an Identity).

Edit: as Damien pointed out, you'll need to add the following line after you define the $sql variable.

mysql_query($sql)