如何只允许注册用户访问他们在mysql数据库中的信息？

Question

I am setting up a student portal for a basci school. In the portal, students should be able to access their grades, courses, course materials, messages from their tutors and also view their payment details and how much they owe the school.

I have mysql tables ( 8 tables in all) with various relationships that is linked to their STUDENT ID.

I want each student to be able to login using username and password - I have the script already with a users table that stores the username and password credentials.

Here are my questions:

1. How to a create a page (php preferred) that will display ALL the information to each student such that each student can ONLY view their records?
2. How do I write the query such that only resources belonging to user can be viewed by that user?
3. There are about 3000 students and each student will register and be able to access their own - grades, Financials (bills and payments), courses, exam results, accommodation issues etc.
4. There are 500 Tutors and they should be able to also access their individual pages such that they can post grades, and generate assignments that will post to all students registered for that course.

Points to note:

1. I have the mysql tables to handle all the information - working.
2. I have the forms with php script to post data to all the forms - working.
3. I have registration and login forms already with their php scripts - working.

The ONLY problem is how to query the relational tables such that each registered user only sees his or her information only. Information is viewed based on the user.

If anyone can point me in the right direction, it would be appreciated. Thank you.

Answer 1

Firstly you dont ask such questions so you wont get down voted and blocked now let me help feel free to contact me and upvote please i am new too and read more on querying database you might not be this lucky next time

   //lets say showstudentsrecordpage.php after they are logged in, you use a cookie a session up to you get their auto incremented ids from database when they log in and query any table you want to with that id

    //create a table so you can show that user info after query

                <table>
    <th>sTUDENT NAME</th>
    <th>sTUDENT rrecord</th>
    <th>sTUDENT subject</th>

           // showstudentsrecordpage.php
           $studentcookieafterloggedin = $_COOKIE['userid']; //userid of student who logged in successfully
          $studentcookieafterloggedin = mysqli_escape_string($con, $studentcookieafterloggedin);

          $bringtheirrecordout = "SELECT FROM mayberecordstable WHERE id= '$studentcookieafterloggedin'";

          $runthequery = mysqli_query($con, $bringtheirrecordout);

        //variable $con is your connection parameters
               if (mysqli_num_rows($runthequery) < 1){
                Do what you want here if that user id is not found probably a redirect or something anything you want
              }

          //you dont need a while loop since it is only one record for a student if it is multiple records for different students then while loop is needed

          $fetcharray = mysqli_fetch_array($runthequery);

  //this are my own parameters just change it to your own database values

                 $id = $fetcharray['id'];
                 $studentname = $fetcharray['studentname'];
                 $studentgrades = $fetcharray['studentgrades'];
                 $subjects = $fetcharray['subjects'];'

          then show it 

        <div>
//continue your table for it here
             <tr>
              <td><?php echo $studentname ?></td>
              <td><?php echo $studentgrades ?></td>
              <td><?php echo $subjects ?></td>
             </tr>
</table>

        </div>