select

<?php
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "bit2018";

// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

$sql = "SELECT * FROM students";
$result = mysqli_query($conn, $sql);

if (mysqli_num_rows($result) > 0)
{

?>
<table border="1" width="600px" height="500px">
<tr>
	<th>S.No.</th>
	<th>Full Name</th>
	<th>Roll No</th>
	<th>Contact</th>
	<th>Address</th>
	<th>Action</th>
</tr>
<?php
// output data of each row
$i =1;
while($row = mysqli_fetch_assoc($result))
	{
?>
<tr>
	<td><?php echo $i; $i++; ?></td>
	<td><?php echo $row['std_fname']." ".$row['std_lname']; ?></td>
	<td><?php echo $row['std_roll']; ?></td>
	<td><?php echo $row['std_contact'];?></td>
	<td><?php echo $row['std_address'];?></td>
	<td>
		<a href="update.php?id=<?php echo $row['std_id'];?>">Edit</a>
		<a href="delete.php?id=<?php echo $row['std_id'];?>">Delete</a>
	</td>
</tr>
 <?php
    }

}
else
{ ?>
<tr>
	<td colspan="5"> No Records Found</td>
</tr>
<?php
}

mysqli_close($conn);
?>
</table>