Contoh Operasi CRUD Codeigniter :

VIEW
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); ?>

<div class="page-title">
	<div class="title_left">
		<h2>
			<i><a href="#"><?php echo $kategori?></a></i>
			<i class="fa fa-angle-double-right"></i>
			<a href="<?php echo site_url($alamat)?>"><?php echo $title?></a>
		</h2>
    </div>
    <div class="title_right">
    	<div class="col-md-8 col-sm-8 col-xs-8">
        	<button type="button" id="btn-tambah" onclick="add()" class="btn btn-success pull-right">
           		<span class="glyphicon glyphicon-plus"></span>  Tambah Data
           	</button>
        </div>
    </div>
</div>
<div class="clearfix"></div>
<br />

<div class="row">
	<div class="col-md-10 col-sm-10 col-xs-10">
		<div class="x-panel">
			<div class="x_title">
				<h2><?php echo $title?></h2>

				<div class="clearfix"></div>
			</div>
			<div class="x_content">
				 <div id="view">
				 	<table id="brand" class="table table-bordered table-striped table-hover">
						<thead>
							<tr class="headings">
								<th>ID</th>
								<th>Brand</th>
								<th>Buatan</th>
								<th>Updated</th>
								<th>Keterangan</th>
								<th colspan = "2" class="text-center"><span class="glyphicon glyphicon-cog"></span></th>
							</tr>
						</thead>
						<tbody>
							<?php
								if ($data_brand->num_rows() > 0)
								{
									$i=1;
									foreach($data_brand->result_array() as $keys=>$key)
									{
										if ($i%2 == 0)
											$class = "odd pointer";
										else $class = "even pointer";
							?>
            				<tr class=<?php echo $class?>>
            					<td class="align-middle"><?php print $key['id_brand']?></td>
                				<td class="align-middle"><?php print $key['brand']?></td>
               	 				<td class="align-middle"><?php print $key['made']?></td>
                				<td class="align-middle"><?php print $key['updated']?></td>
                				<td class="align-middle"><?php print $key['keterangan']?></td>
                				<td class="align-middle text-center">
                					<a href="javascript:void();" onclick="edit(<?php echo $key['id_brand']; ?>);" class="btn btn-default" title="Edit"><span class="glyphicon glyphicon-pencil"></span></a>
                				</td>
                				<td class="align-middle text-center">
               						<a href="javascript:void();" onclick="hapus(<?php echo $key['id_brand']; ?>);" class="btn btn-danger" title="Delete"><span class="glyphicon glyphicon-erase"></span></a>
               					</td>
            				</tr>
            				<?php
									$i++;
									}
                  				}
            				?>
                   		</tbody>
					</table>
				 </div>
			</div>
		</div>
	</div>
</div>



<script>
$(document).ready( function () {
    $('#brand').DataTable();
});

var save_method;
var table;

function add()
{
  save_method = 'add';
  $('#form')[0].reset(); // reset form on modals
  $('#form-modal').modal('show'); // show bootstrap modal
//$('.modal-title').text('Add Person'); // Set Title to Bootstrap modal title
}

function edit(id)
{
  save_method = 'update';
  $('#form')[0].reset(); // reset form on modals

  //Ajax Load data from ajax
  $.ajax({
    url : "<?php echo site_url('brand/ajax_edit/')?>/" + id,
    type: "GET",
    dataType: "JSON",
    success: function(data)
    {
        $('[name="id_brand"]').val(data.id_brand).attr("readonly","readonly");
        $('[name="brand"]').val(data.brand).attr("readonly","readonly");
        $('[name="made"]').val(data.made);
        $('[name="keterangan"]').val(data.keterangan);

        $('#form-modal').modal('show'); // show bootstrap modal when complete loaded
        $('.modal-title').text('Edit Brand'); // Set title to Bootstrap modal title

    },
    error: function (jqXHR, textStatus, errorThrown)
    {
        alert('Error get data from ajax');
    }
});
}

function save()
{
  var url;
  if(save_method == 'add')
  {
      url = "<?php echo site_url('brand/tambah')?>";
  }
  else
  {
    url = "<?php echo site_url('brand/edit')?>";
  }

   // ajax adding data to database
      $.ajax({
        url : url,
        type: "POST",
        data: $('#form').serialize(),
        dataType: "JSON",
        success: function(data)
        {
           //if success close modal and reload ajax table
           $('#form_modal').modal('hide');
          location.reload();// for reload a page
        },
        error: function (jqXHR, textStatus, errorThrown)
        {
            alert('Error adding / update data');
        }
    });
}

function hapus(id)
{
  if(confirm('delete this data?'))
  {
    // ajax delete data from database
      $.ajax({
        url : "<?php echo site_url('brand/konfirm')?>/"+id,
        type: "POST",
        dataType: "JSON",
        beforeSend: function(e) {
        	if(e && e.overrideMimeType) {
         		e.overrideMimeType("application/json;charset=UTF-8");
        		}
      	},
        success: function(response)
        {
        	alert(response.pesan);
			$("#view").html(response.html);
			location.href = location.pathname;
        },
        error: function (jqXHR, textStatus, errorThrown)
        {
            alert('Error deleting data');
        }
    });

  }
}

$(document).ready(function(){

	$('#form-modal').on('hidden.bs.modal', function (e){
        $("#btn-reset").click();
        $("#brand").removeAttr('readonly');
    });
});
</script>

<!-- Bootstrap modal -->
  <div class="modal fade" id="form-modal" role="dialog">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
        <h3 class="modal-title">Form Data Brand</h3>
      </div>
      <div class="modal-body form">
        <form action="#" id="form" class="form-horizontal">
          <input type="hidden" value="" name="id_brand"/>
          <div class="form-body">
            <div class="form-group">
              <label class="control-label col-md-3">Brand</label>
              <div class="col-md-9">
                <input name="brand" placeholder="Nama Brand" class="form-control" type="text">
              </div>
            </div>
            <div class="form-group">
              <label class="control-label col-md-3">Made/Buatan</label>
              <div class="col-md-9">
                <input name="made" placeholder="Made/Buatan" class="form-control" type="text">
              </div>
            </div>
			<div class="form-group">
				<label class="control-label col-md-3">Keterangan</label>
				<div class="col-md-9">
					<textarea rows="6" cols="3" name="keterangan" class="form-control"></textarea>
				</div>
			</div>
          </div>
        </form>
          </div>
          <div class="modal-footer">
            <button type="button" id="btnSave" onclick="save()" class="btn btn-primary">Simpan</button>
            <button type="button" class="btn btn-danger" data-dismiss="modal">Cancel</button>
          </div>
        </div><!-- /.modal-content -->
      </div><!-- /.modal-dialog -->
    </div><!-- /.modal -->
  <!-- End Bootstrap modal -->

CONTROLLER
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Brand extends CI_Controller
{
	private $table 		= 'tb_brand';
	private $primary 	= 'id_brand';

	function __construct()
	{
		parent::__construct();
		$this->load->library(array('template'));

		$user = $this->session->userdata('username');
		if ($user)
		{
			$lvl = $this->session->userdata('level');
			if($lvl != '1')
			{
				redirect('dashboard/index');
			}
		}
		else redirect('web');
	}

	function index()
	{
		$lvl  = $this->session->userdata('level');
		$kategori = $this->_get_nama($lvl);

		$data_brand = $this->m_all->semua($this->table);

	    $data['kategori'] = $kategori;
	    $data['alamat'] = 'brand/index';
	    $data['data_brand'] = $data_brand;
	    $data['title']="List Brand";

	    $this->template->display('brand/index',$data);
	 }

	 function tambah()
	 {
	  	$brand = db_clean($this->input->post('brand'));
	  	$made = db_clean($this->input->post('made'));

	  	if ($brand and $made)
	  	{
	  		$cek = $this->m_all->cari($brand, $made, '','','','brand','made','',$this->table);
	  		if ($cek->num_rows() > 0)
	  			$response = array('status'=>'gagal','pesan'=>'Data brand telah tersedia');
	  		else
	  		{
	  			$info = array(
	  				'id_brand'		=> $this->auth->get_jumlah($this->primary, $this->table) + 1,
	  				'brand' 		=> $brand,
	  				'made'			=> $made,
	  				'keterangan'	=> db_clean($this->input->post('keterangan')),
	  				'updated'		=> $this->session->userdata('nama').'-'.date('Y-m-d H:i:s')
	  			);

	  			$this->m_all->simpan($info, $this->table);

	  			ob_start();
	  			$html = ob_get_contents();
	  			ob_end_clean();

	  			$response = array('status'=>'true','pesan'=>'Data berhasil disimpan', 'html'=>$html);
	  		}
	  	}
	  	else $response = array('status'=>'false','pesan'=>'Data brand dan Made kosong');

	  	echo json_encode($response);
	 }

	 function ajax_edit($id)
	 {
	 	$data = $this->m_all->get_by_id($this->table, $this->primary, $id);

	 	echo json_encode($data);
	 }

	 function edit()
	 {
	 	$kode = $this->input->post('id_brand');
	 	$made = db_clean($this->input->post('made'));

	 	if ($kode and $made)
	 	{
	 		$cek = $this->m_all->cek($kode, $this->primary, $this->table);
	 		foreach ($cek->result() as $row)
	 		{
	 			$updated = $row->updated;
	 		}

	 		$info = array(
	 				'made'			=> $made,
	 				'keterangan'	=> db_clean($this->input->post('keterangan')),
	 				'updated'		=> $updated.';'.$this->session->userdata('nama').'-'.date('Y-m-d H:i:s')
	 		);

	 		$this->m_all->update($kode, $info, $this->primary, $this->table);

	 		ob_start();
	 		$html = ob_get_contents();
	 		ob_end_clean();

	 		$response = array('status'=>'true','pesan'=>'Data berhasil di-ubah', 'html'=>$html);
	 	}
	 	else $response = array('status'=>'false','pesan'=>'Data gagal di-ubah');

	 	echo json_encode($response);
	 }

	 function konfirm($id)
	 {
	 	$cek = $this->m_all->cek($id, 'brand', 'tb_itemofbasic');
	 	if ($cek->num_rows() > 0)
	 	{
	 		foreach ($cek->result() as $row)
	 		{
	 			$aktif = $row->aktif;
	 		}
	 	}
	 	else $aktif = 0;

	 	if ($aktif == 0)
	 	{
	 		$this->m_all->hapus($id, '', $this->primary, '',$this->table);

	 		ob_start();
	 		$html = ob_get_contents();
	 		ob_end_clean();

	 		$response = array('status'=>'true', 'pesan'=> 'Data berhasil di-hapus','html'=>$html);
	 	}
	 	else $response = array('status'=>'false','pesan'=>'Data product atas brand, aktif');

	 	echo json_encode($response);
	 }

	 function _get_nama($lvl)
	 {
	 	$get_nm_lvl = $this->m_all->getNama('level', $lvl, null, 'level_nama', 'id_level');
	 	if ($get_nm_lvl->num_rows() > 0)
	 	{
	 		foreach ($get_nm_lvl->result() as $gnl)
	 		{
	 			$p = $gnl->level_nama;
	 		}
	 	}
	 	else $p = '';
	 	return $p;
	 }


}