simple else with while in loop not working - php

Question

My code is working as for my needs. But the only thing bugging me is
the "else" is not working. When i search for a correct record the
record will appear and it was running fine. But if i Incorrectly
search a record nothing will happen. i am expecting "Records not Found" will echo but nothing happen.
}else{
echo "Records not found";
}
This is the whole code.
<?php
$conn = mysqli_connect("localhost", "root", "", "my1stdb") or die("could not connect");
$set = $_POST['search'];
if ($set) {
$show = "SELECT * FROM users where email='$set'";
$result = mysqli_query($conn, $show);
while ($rows = mysqli_fetch_array($result)) {
echo "Registrant Found";
echo "<tr>";
echo "<td>";
echo $rows['username'];
echo "</td>";
echo "<td>";
echo $rows['fullname'];
echo "</td>";
echo "<td>";
echo $rows['password'];
echo "</td>";
echo "<td>";
echo $rows['email'];
echo "</td>";
echo "</tr>";
echo "<br/>";
}
} else {
echo "Records not found";
}
?>
</table>

Answer 1

You need to use mysqli_num_rows() along with mysqli_fetch_assoc():-
<?php
$conn=mysqli_connect("localhost","root","","my1stdb") or die("could not connect");
$set = $_POST['search'];
if($set) {
$show="SELECT * FROM users where email='$set'";
$result=mysqli_query($conn,$show) or die(mysqli_error($conn));
if(mysqli_num_rows($result)>0){ // check data present or not
while($rows=mysqli_fetch_assoc($result)){ // for lighter array due to associative indexes only
echo "Registrant Found";
echo "<tr>";
echo "<td>";
echo $rows['username'];
echo "</td>";
echo "<td>";
echo $rows['fullname'];
echo "</td>";
echo "<td>";
echo $rows['password'];
echo "</td>";
echo "<td>";
echo $rows['email'];
echo "</td>";
echo "</tr>";
echo "<br/>";
}
}else{
echo "Records not found";
}
}else{
echo "Please insert search term";
}
?>
</table>
Note:- Your code is wide-open for SQL INJECTION. to prevent from it use prepared statements
Reference:-
mysqli prepared statements
PDO prepared statements

Answer 2

You could count the number of results returned.
if($set) {
$show="SELECT * FROM users where email='$set'";
$result=mysqli_query($conn,$show);
$recordCount = 0;
while($rows=mysqli_fetch_array($result)){
$recordCount++;
echo "Registrant Found";
echo "<tr>";
echo "<td>";
echo $rows['username'];
echo "</td>";
echo "<td>";
echo $rows['fullname'];
echo "</td>";
echo "<td>";
echo $rows['password'];
echo "</td>";
echo "<td>";
echo $rows['email'];
echo "</td>";
echo "</tr>";
echo "<br/>";
}
if($recordCount==0){
echo "Records not found";
}
}