I want to compare post values like php, java with the value stored in database table name courses and field name subjects and it has values php, java, c++. After comparing all values it must give results like courses already taken.
I want to store values then if values available then compare values and if new value the store these values along with old values.
1 . Store values --> Done
2. Compare values --> Is my problem
3. Store new values with old values --> Done
<pre><?php
include './connect.php';
echo "<form action='admin.php?page=selectcourse' method='POST'>";
echo "<h1>Assign Course to Students</h1>";
$res=mysqli_query($conn, "SELECT * FROM inputcourses");
$counter = 1;
$product_count = mysqli_num_rows ($res);
if ($product_count > 0) {
while($row=mysqli_fetch_array($res))
{?>
<br/>
<input type="checkbox" name="coursename[]" value=" <?php echo $row['coursename']; ?>"> <?php echo $row['coursename']; ?>
<?php
$counter++;
}
}
else
{
echo "No Course Found";
}
echo "<h1>Select Student</h1>";
$res=mysqli_query($conn, "SELECT * FROM registration");
$counter = 1;
$student_count = mysqli_num_rows ($res);
if ($student_count > 0) {
echo "<table border=1 width='800px'>";
echo "<tr>
<td></td>
<td>Sr no.</td>
<td>Name</td>
<td>Student ID</td>
</tr>";
while($row=mysqli_fetch_array($res))
{
echo "<tr>
<td><input type='radio' name='rname' value='".$row['id']."'></td>
<td>".$counter."</td>
<td><input type='text' name='name' value='".$row['first_name'].' '.$row['last_name']."' readonly></td>
<td><input type='text' name='id' value='".$row['id']."' readonly></td>
</tr>";
$counter++;
}
echo "</table>";
}
else
{
echo "No Student Found";
}
echo "<input type='submit' name='submit' value='Submit'>";
echo "</form>";
?>
<pre><?php
include 'connect.php';
if (isset($_POST['submit'])) {
$id = mysqli_real_escape_string($conn, $_POST['rname']);
$checkBox = strtoupper(implode(',', $_POST['coursename']));
$res=mysqli_query($conn, "SELECT * FROM registration WHERE id='$id'");
$row=mysqli_fetch_array($res);
$newval = $row['subjects'].','.$checkBox;
if (empty($row['subjects'])) {
# code...
$result1=mysqli_query($conn, "UPDATE registration set subjects='" . $checkBox. "' WHERE id = '".$id."'");
if ($result1) {
# code...
header("Location: admin.php?page=assigncourse&&message=done from with empty");
}
else
{
header("Location: admin.php?page=assigncourse&&message=not done");
}
}
elseif (!empty($row['subjects'])) {
# code...
$res=mysqli_query($conn, "SELECT * FROM registration WHERE FIND_IN_SET('php', subjects)");
if ($res) {
# code...
echo "taken";
}
else{
$result1=mysqli_query($conn, "UPDATE registration set subjects='" . $newval. "' WHERE id = '".$id."'");
if ($result1) {
# code...
header("Location: admin.php?page=assigncourse&&message=done from else");
}
else
{
header("Location: admin.php?page=assigncourse&&message=not done");
}
}
}
}
?>