JQuery Datatable Server Side Processing

<!-- Custom page script -->
    <script>
        var selected = [];
        $(function () {           
            $('#emailTemplatesDataTable').DataTable({
                "paging": true,
                "lengthChange": true,
                "searching": true,
                "ordering": true,
                "info": true,
                "autoWidth": false,
                order: [[0, 'DESC']],
                columnDefs: [
                     { orderable: false, targets: 0 },
                     { orderable: false, targets: 1 },
                     { orderable: false, targets: 2 },
                     { orderable: false, targets: 3 }, 
                     { "width": "5%", "targets": 2 },
                     { "width": "10%", "targets": 3 },                        
                     { "className": "dt-center", "targets": 2 },
                     { "className": "dt-center", "targets": 3 }  
                 ],
                "drawCallback": function (settings) {
                    $("#emailTemplatesDataTable").wrap("<div class='table-responsive'></div>");
                    $('[data-toggle=confirmation]').confirmation({
                        rootSelector: '[data-toggle=confirmation]'                    
                      });
                },               
                "fnRowCallback": function( nRow, aData) {
                    $(nRow).attr("rowid", aData[4]);
                    return nRow;
                },
                "bProcessing": true,
                "serverSide": true,
                "language": {
                                 "processing": '<img src="<?php echo BACKEND_URL; ?>/images/lazy-loader.gif">'
                             },                
                "ajax":{
                    url :"ajax/response_email_template.php",
                    type: "post"
                  }                          
            });
            $('#emailTemplatesDataTable tbody').on('click', 'tr', function () {
                var id = $(this).attr('rowid');
                var index = $.inArray(id, selected);

                if ( index === -1 ) {
                    selected.push( id );
                } else {
                    selected.splice( index, 1 );
                }                
                console.log(selected);
                $(this).toggleClass('selected');
            } );
            
        });
    </script>    

    <!-- CHANGE STATUS OF RECORD USING AJAX -->
    <script>
        $(document).on('click','.ChangeStatus',function(e){           
           var id = $(this).attr('id');
           var status = $(this).attr('status');
           var Data = 'action_type=changestatus&table=email_templates&id='+id+'&status='+status;
               $.ajax({
                type: 'POST',
                url: 'ajax/masterChangeStatus.php',
                data: Data,
                success:function(){
                    var table = $('#emailTemplatesDataTable').DataTable();
                    table.ajax.reload(); 
                }
            });
        });
    </script>
    
    <!-- DELETE ONE RECORD USING AJAX -->
    <script>
        $(document).on('click','.delete',function(e){
           var id = $(this).attr('id');
           var Data = 'action_type=delete&table=email_templates&id='+id;
               $.ajax({
                type: 'POST',
                url: 'ajax/masterChangeStatus.php',
                data: Data,
                success:function(){
                    var table = $('#emailTemplatesDataTable').DataTable();
                    table.ajax.reload(); 
                }
            });
        });
    </script>
    
    <!--MULTIPLE DELETE RECORD USING AJAX -->
    <script>
        $(document).on('click','#delete',function(){           
           var rowIds = selected;
           var Data = 'action_type=multipledelete&table=email_templates&rowIds='+rowIds;
               $.ajax({
                type: 'POST',
                url: 'ajax/masterChangeStatus.php',
                data: Data,
                success:function(){                    
                    var table = $('#emailTemplatesDataTable').DataTable();
                    table.ajax.reload(); 
                }
            });            
        });
    </script>
    
    <script>
        $(document).on('click','#selectAll',function(){
            var table = $('#emailTemplatesDataTable').DataTable();
            table.rows().iterator( 'row', function ( context, index ) {               
                $( this.row( index ).node() ).addClass( 'selected' );
                
                var id = $( this.row( index ).node() ).attr('rowid');
                var index = $.inArray(id, selected);
                
                if ( index === -1 ) {
                    selected.push( id );
                } else {
                    //selected.splice( index, 1 );
                }                
            } ); 
            console.log(selected);
        });
    </script>
    
    <script>
        $(document).on('click','#deSelectAll',function(){
            var table = $('#emailTemplatesDataTable').DataTable();
            table.rows().iterator( 'row', function ( context, index ) {               
                $( this.row( index ).node() ).removeClass( 'selected' );
                var id = $( this.row( index ).node() ).attr('rowid');
                var index = $.inArray(id, selected);
                
                if ( index === -1 ) {
                    //selected.push( id );
                } else {
                    selected.splice( index, 1 );
                }                                   
            } );
            console.log(selected);
        });
    </script>

Scroll Loading Server Side Processing PHP File

<?php
error_reporting(E_ALL ^ E_NOTICE);
ob_start();
session_start();

include 'config.php';

// storing  request (ie, get/post) global array to a variable  
$requestData= $_REQUEST;
$type = $_REQUEST['type'];

$columns = array( 
// datatable column index  => database column name
	0 => '', 
	1 => ''
);

// getting total number records without any search
$sql = "SELECT * FROM media WHERE type = '$type' ORDER BY created_on DESC";
$query = mysqli_query($conn, $sql) or die("response_media.php: get event media");
$totalData = mysqli_num_rows($query);
$totalFiltered = $totalData;  // when there is no search parameter then total number rows = total number filtered rows.


//$sql = "SELECT * FROM media";

//if( !empty($requestData['search']['value']) ) {   // if there is a search parameter, $requestData['search']['value'] contains search parameter
//	$sql.=" AND ( employee_name LIKE '".$requestData['search']['value']."%' ";    
//	$sql.=" OR employee_salary LIKE '".$requestData['search']['value']."%' ";
//	$sql.=" OR employee_age LIKE '".$requestData['search']['value']."%' )";
//}

//$query = mysqli_query($conn, $sql) or die("response_media.php: get event media");
//$totalFiltered = mysqli_num_rows($query); // when there is a search parameter then we have to modify total number filtered rows as per search result. 
//$sql.= " LIMIT ".$requestData['start']." ,".$requestData['length']." "; 
//$query = mysqli_query($conn, $sql) or die("response_media.php: get event media");
	

$data = array();
while( $row = mysqli_fetch_array($query) ) {  // preparing an array
	$nestedData=array(); 
        
        $path_info = pathinfo($row['path']);
        $ext = $path_info['extension']; 
        if ( $row['type'] == 'image' ) {
            $nestedData[] = '<img src="timthumb.php?src='.$row['path'].'&w=60&h=40">';                    
        }else{
            $nestedData[] = '<a href="'.$row['path'].'" target="_blank"><i class="fa fa-file-text-o"></i> &nbsp;'.substr($row['name'], 0,35).'</a>';                    
        }	
        $nestedData[] = '<span class="btn btn-danger btn-xs delete" id="'.$row['id'].'" path="'.$row['path'].'" data-toggle="confirmation" data-title="Do you want to delete ?" data-placement="left"><i class="fa fa-trash"></i></span>';	
	
	$data[] = $nestedData;
}

$json_data = array(
			"draw"            => intval( $requestData['draw'] ),   // for every request/draw by clientside , they send a number as a parameter, when they recieve a response/data they first check the draw number, so we are sending same number in draw. 
			"recordsTotal"    => intval( $totalData ),  // total number of records
			"recordsFiltered" => intval( $totalFiltered ), // total number of records after searching, if there is no searching then totalFiltered = totalData
			"data"            => $data   // total data array
			);

echo json_encode($json_data);  // send data as json format

?>

Server Side Processing PHP File

<?php
error_reporting(E_ALL ^ E_NOTICE);
ob_start();
session_start();

include 'config.php';

// initilize all variable
$params = $columns = $totalRecords = $data = array();
$params = $_REQUEST;

//define index of column
$columns = array(
    0 => 'name',
    1 => 'image',
    2 => 'created_on');


$sqlTot = $sqlRec = $share = "";

// check search value exist
if (!empty($params['search']['value'])) {
    $where .= " WHERE ";
    $where .= " AND name LIKE '" . $params['search']['value'] . "%' ";
}

// getting total number records without any search
$sql = "SELECT id,title,image,status,created_on FROM books";
$sqlTot .= $sql;
$sqlRec .= $sql;

//concatenate search sql if value exist
if (isset($where) && $where != '') {

    $sqlTot .= $where;
    $sqlRec .= $where;
}

$sqlRec .= " ORDER BY ". $columns[$params['order'][0]['column']]." ".$params['order'][0]['dir']." LIMIT " . $params['start'] . " ," . $params['length'] . " ";

$queryTot = mysqli_query($conn, $sqlTot) or die("database error:" . mysqli_error($conn));

$totalRecords = mysqli_num_rows($queryTot);

$queryRecords = mysqli_query($conn, $sqlRec) or die("error to fetch selling company data");

//iterate on results row and create new index array of data
while ($row = mysqli_fetch_assoc($queryRecords)) {
    $nestedData = array();
   
    $nestedData[] = $row['title'];
    $nestedData[] = '<img src="timthumb.php?src='.$row['image'].'&h=100&w=80&zc=3">';
    $nestedData[] = date('d-m-Y', strtotime($row['created_on']));
    
    if ( $row['status'] == 1 ) {
        $nestedData[] = '<span class="btn btn-success btn-xs ChangeStatus" id="'.$row['id'].'" status ="'.$row['status'].'" data-toggle="confirmation" data-title="Do you want to change status ?" data-placement="left"><i class="fa fa-check"></i></span>';
    } else {
        $nestedData[] = '<span class="btn btn-danger btn-xs ChangeStatus" id="'.$row['id'].'" status ="'.$row['status'].'" data-toggle="confirmation" data-title="Do you want to change status ?" data-placement="left"><i class="fa fa-times"></i></span>';
    }
    
    $nestedData[] = '<a href="review_book.php?id='.$row['id'].'" class="btn btn-warning btn-xs"><i class="fa fa-quote-left"></i></a> <a href="manage_book.php?id='.$row['id'].'" class="btn btn-primary btn-xs"><i class="fa fa-eye"></i></a> <span class="btn btn-danger btn-xs delete" id="'.$row['id'].'" data-toggle="confirmation" data-title="Do you want to delete ?" data-placement="left"><i class="fa fa-trash"></i></span>';
    
    $data[] = $nestedData;
}

$json_data = array(
    "draw" => intval($params['draw']),
    "recordsTotal" => intval($totalRecords),
    "recordsFiltered" => intval($totalRecords),
    "data" => $data   // total data array
);

echo json_encode($json_data);  // send data as json format