Joining three tables and displaying value using php - php

Question

I have used join and was able to get output table in phpmyadmin using this query :
$query = "SELECT members.usn, members.name, events.ename FROM members JOIN participant ON members.usn = participant.usn JOIN events ON events.eid = participant.eid WHERE members.usn='.$usn.'";
$result = $conn->query($query);
The Output was
usn
name
ename
7DC18CS005
John
Robo Wars
I used PHP to display this in my homepage for specific user by maintaining usn in their SESSION.
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
echo '<tr>';
echo '<td>';
echo $row[0];
echo '</td>';
echo '<td>';
echo $row[1];
echo '</td>';
echo '<td>';
echo $row[2];
echo '</td>';
echo '</tr>';
}
} else {
echo "No Members[Connected DB]";
}
But the output gives me
"No Members[Connected DB]"
instead of expected output which is
usn
name
ename
7DC18CS005
John
Robo Wars
Thank you!

Answer 1

You have a typo in the query. Looks like you are trying to concatenate $usn to the query but you got it wrong.
Change
$query = "SELECT members.usn, members.name, events.ename FROM members JOIN participant ON members.usn = participant.usn JOIN events ON events.eid = participant.eid WHERE members.usn='.$usn.'";
To
$query = "SELECT members.usn, members.name, events.ename FROM members JOIN participant ON members.usn = participant.usn JOIN events ON events.eid = participant.eid WHERE members.usn='$usn'";