Change code from mysql to mssql in a php file

Question

I'm new to php and sql.

The codes below are written in php and working fine when connecting to a mysql database. SELECT query is working and UPDATE query is working.

But when connecting to an mssql database, the codes don't work well. I need to convert them to connect to a similar mssql database. Thank you.

---

 <table id="data_table" class="table table-striped">
    <thead>
        <tr>
            <th>Id</th>
            <th>Name</th>
            <th>Gender</th>
            <th>Age</th>    
            <th>Designation</th>
            <th>Address</th>
        </tr>
    </thead>
    <tbody>
        <?php 
        $sql_query = "SELECT id, firstname, lastname, address, email FROM 
     myguests LIMIT 10";
        $resultset = mysqli_query($conn, $sql_query) or die("database 
     error:". mysqli_error($conn));
        while( $developer = mysqli_fetch_assoc($resultset) ) {
        ?>
           <tr id="<?php echo $developer ['id']; ?>">
           <td><?php echo $developer ['id']; ?></td>
           <td><?php echo $developer ['firstname']; ?></td>
           <td><?php echo $developer ['lastname']; ?></td>
           <td><?php echo $developer ['address']; ?></td>   
           <td><?php echo $developer ['email']; ?></td>

               </tr>
            <?php } ?>
        </tbody>
      </table>  

---

<?php
/* Database connection start */
$servername = "*****";
$username = "*****";
$password = "*****";
$dbname = "*****";
  $conn = mysqli_connect($servername, $username, $password, $dbname) or 
  die("Connection failed: " . mysqli_connect_error());
 if (mysqli_connect_errno()) {
   printf("Connect failed: %s\n", mysqli_connect_error());
  exit();
  }
 ?>

---

   <?php
   include_once("db_connect.php");
   $input = filter_input_array(INPUT_POST);
   if ($input['action'] == 'edit') {    
    $update_field='';
   if(isset($input['firstname'])) {
    $update_field.= "firstname='".$input['firstname']."'";
    } else if(isset($input['lastname'])) {
    $update_field.= "lastname='".$input['lastname']."'";
   } else if(isset($input['address'])) {
    $update_field.= "address='".$input['address']."'";
     } else if(isset($input['email'])) {
    $update_field.= "email='".$input['email']."'";

       }    
        if($update_field && $input['id']) {
        $sql_query = "UPDATE myguests SET $update_field WHERE id='" . 
          $input['id'] . "'";   
            mysqli_query($conn, $sql_query) or die("database error:". 
          mysqli_error($conn));     
              }
              }

Answer 1

The rough equivalent of MySQL LIMIT in SQL Server is TOP , so you may try something like:

SELECT TOP 10 id, firstname, lastname, address, email
FROM myguests
ORDER BY <some_column>;

Note carefully that I added an ORDER BY clause to your query. Using LIMIT (or TOP ) without ORDER BY is fairly meaningless, because you haven't told SQL which 10 rows you want, relative to some ordering.