========== HTML =================
<table id="example" class="display" cellspacing="0" width="100%">
  <thead>
    <tr>
      <th>Sr.</th>
      <th>Branch</th>
    </tr>
  </thead>
</table>

[in footer]
(document).ready(function() {
    $('#example').DataTable( {
        "ajax": '<?php echo base_url(); ?>Batch/batchtable'
    } );

========== HTML =================

========== Controller =================
public function batchtable(){

		$batchdata = $this->model->batchdetail();

		$data=array();
		$x=1;
		foreach($batchdata as $batch_data) {
			$encrypted_id = $this->model->encryptdata($batch_data['batch_id']);
			$coursename=$batch_data['course'];

			$data[] = array(
						$x,
						$batch_data['branch_name'],
		                $batch_data['batch_name'],
		                array_column($coursename, 'course_name'),
		                $batch_data['startdate'],
		                $batch_data['enddate'],
		                $batch_data['maximum_student'],
		                $batch_data['active'],
		                "
		                <a href='".base_url()."Batch/viewbatch/".$encrypted_id."' class='EditBtn btn green btn-sm'>
											<span class='glyphicon glyphicon-eye-open'></span>
										</a>
		                <a href='".base_url()."Batch/editbatch/".$encrypted_id."' class='EditBtn btn green btn-sm'>
											<span class='glyphicon glyphicon-pencil'></span>
										</a>
										<a href='".base_url()."Batch/deletebatch/".$encrypted_id."' data-toggle='confirmation' id='deleteadd' data-placement='left' class='btn red btn-sm deleteconform'>
										  <span class='glyphicon glyphicon-trash'></span>
										</a>"
		            );
			$x++;
		}
		$output = array(
		                "data" => $data
		            );
        echo json_encode($output);
      	exit();
	}
========== Controller =================