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Cannot display the table from database

It cannot display the table from database. For each program there is a table, in which some scores are saved. Plus, there is a program table in which program id and program name are saved. When I selected a program and a year I got the following errors:

No data found

Notice: Undefined variable: result in C:\\XAMPP\\htdocs\\statistics\\ac_directorPrograms.php on line 61

Warning: mysql_fetch_assoc() expects parameter 1 to be resource, null given in C:\\XAMPP\\htdocs\\statistics\\ac_directorPrograms.php on line 61

Something goes wrong with the result from the action code and I guess with the prog_name and program form the form.

The form:

   <?php 
      include 'connect.php'; 
   ?>
    <form name="myform" action="ac_directorPrograms.php" method="POST">

      <b>Programs:<b/>
        <select name="program"> 
        <option value="Choose">Please select..</option>
        <?php
                $sql = mysql_query("SELECT prog_name FROM program");
                while ($row = mysql_fetch_array($sql)) {
                echo "<option value='" . $row['prog_name'] . "'>" .    $row['prog_name'] ."</option>";
                }
        ?>  
         </select><br/><br/>

<b>Year:<b/>
<select name="year"> 
<option value="Choose">Please select..</option>
<option value="2005">2005</option> 
<option value="2006">2006</option>
<option value="2007">2007</option></select><br/><br/>


<br/>
<input type="submit" value="submit" name="Submit">
<input type="reset" name="reset" value="Clear">

</form>
</div>

the action code

      <?php 

        include 'connect.php';

        $year = $_POST['year'];
        $program = $_POST['program']; 
        $years     = array(
            2005,
            2006,
            2007
       );
       $programs = array(
          'bsc computer science',
          'bsc psychology',
          'ba finance',
          'ba marketing',
          'ba management'
       );

       if (in_array($program, $programs) && in_array($year, $years)) {

          $sql = "SELECT a1,a2,a3,l1,l2,l3,l4,l5,l6,l7,lavg,r1,r2,u1,u2,u3 FROM $program WHERE year=$year";

            $result = mysql_query($sql);
      }

      else {
            echo "No data found";
     }
     ?>
        <html>
         <head>
         <link rel="stylesheet" type="text/css" href="../../statistics/style.css">
         </head>
          <body>

           <div id="container">
            <table id="table" width="900" border="1" cellspacing="1">

             <tbody>
               <tr>
                <td>A1 </td>
                <td>A2 </td>
                <td>A3 </td>
                <td>L1 </td>
                <td>L2 </td>
                <td>L3 </td>
                <td>L4 </td>
                <td>L5 </td>
                <td>L6 </td>
                <td>L7 </td>
                <td>LAVG </td>
                 <td>R1 </td>
                <td>R2 </td>
                <td>U1 </td>
                <td>U2 </td>
               <td>U3 </td>
         </tr>
       </tbody>
       <?php
              while($program=mysql_fetch_assoc($result)){
                   echo "<tr>";
                   echo "<td>".$program['a1']."</td>";
                   echo "<td>".$program['a2']."</td>";
                   echo "<td>".$pprogram['a3']."</td>";
                   echo "<td>".$pprogram['l1']."</td>";
                   echo "<td>".$program['l2']."</td>";
                   echo "<td>".$program['l3']."</td>";
                   echo "<td>".$program['l4']."</td>";
                   echo "<td>".$program['l5']."</td>";
                   echo "<td>".$program['l6']."</td>";
                   echo "<td>".$program['l7']."</td>";
                   echo "<td>".$program['lavg']."</td>";
                   echo "<td>".$program['r1']."</td>";
                   echo "<td>".$program['r2']."</td>";
                   echo "<td>".$program['u1']."</td>";
                   echo "<td>".$program['u2']."</td>";
                   echo "<td>".$program['u3']."</td>";
                  echo "</tr>";    
               }
            ?>
      </table>
    </div>
   </body>
   </html>

In the action code and after the include connect.php , add this... $con=mysqli_connect("localhost","my_user","my_password","my_db"); and dont forget to replace my_user , my_password , my_db with yours user, password and database name.

Also replace this code $result = mysql_query($sql); with this one $result=mysqli_query($con,$sql);

This is the issue of scope of the variable. You have defined $result inside if condition and using that out side of if. You need to define $result out side of if condition.

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