Unable to save multi selected values to db from magento admin form and render it to grid

Question

I have created a custom grid, I need to add a multi select field. Multi select field will be getting value from "customer_group" table as you can see in

/www/Abc/app/code/local/Abc/Bar/Block/Adminhtml/Baz/Edit/Form.php,

I am unable to save my multi selected values to to db(abc_bar/baz) in field "customer_group_id" and render them in grid,

my db looks like this

    /app/code/local/Abc/Bar/sql/abc_bar_setup/mysql4-install-1.0.0.php
<?php
$installer = $this;
$installer->startSetup();
    $table = $installer->getConnection()
        ->newTable($installer->getTable('abc_bar/baz'))
        ->addColumn('id', Varien_Db_Ddl_Table::TYPE_INTEGER, null, array(
            'identity'  => true,
            'unsigned'  => true,
            'nullable'  => false,
            'primary'   => true,
            ), 'ID')
        ->addColumn('name', Varien_Db_Ddl_Table::TYPE_CLOB, 0, array(
            'nullable'  => false,
            ), 'Name')
->addColumn($installer->getTable('abc_bar_baz'), 'emails', array(
            'type' => Varien_Db_Ddl_Table::TYPE_TEXT,
            'comment' => 'Sales Emails for Order type'
                )
->addColumn($installer->getTable('abc_bar_baz'), 'ordertype_description', array(
            'type' => Varien_Db_Ddl_Table::TYPE_TEXT,
            'comment' => 'Order type description'
                )
 ->addColumn($installer->getTable('abc_bar_baz'), 'customer_group_id', array(
            'type' => Varien_Db_Ddl_Table::TYPE_INTEGER,
            'length' => 11,
            'nullable' => false,
            'comment' => 'customer group to bind order type'
                )

;
    $installer->getConnection()->createTable($table);
    $installer->endSetup();

and my grid is

    www/Abc/app/code/local/abc/Bar/Block/Adminhtml/Baz/Grid.php
<?php

class Abc_Bar_Block_Adminhtml_Baz_Grid extends Mage_Adminhtml_Block_Widget_Grid {

public function __construct() {
    parent::__construct();
    $this->setDefaultSort('id');
    $this->setId('abc_bar_baz_grid');
    $this->setDefaultDir('asc');
    $this->setSaveParametersInSession(true);
}

protected function _getCollectionClass() {
    return 'abc_bar/baz_collection';
}

protected function _prepareCollection() {
    $collection = Mage::getResourceModel($this->_getCollectionClass());
    $this->setCollection($collection);

    return parent::_prepareCollection();
}

protected function _prepareColumns() {
    $this->addColumn('id', array(
        'header' => $this->__('ID'),
        'align' => 'right',
        'width' => '50px',
        'index' => 'id'
            )
    );

    $this->addColumn('name', array(
        'header' => $this->__('Name'),
        'index' => 'name'
            )
    );

    return parent::_prepareColumns();
}

public function getRowUrl($row) {
    return $this->getUrl('*/*/edit', array('id' => $row->getId()));
}
}

And my form is

/www/Abc/app/code/local/Abc/Bar/Block/Adminhtml/Baz/Edit/Form.php
class Abc_Bar_Block_Adminhtml_Baz_Edit_Form extends Mage_Adminhtml_Block_Widget_Form {
public function __construct() {
    parent::__construct();

    $this->setId('abc_bar_baz_form');
    $this->setTitle($this->__('Baz Information'));
}



 protected function _prepareForm() {
        $model = Mage::registry('abc_bar');

        $form = new Varien_Data_Form(array(
            'id' => 'edit_form',
            'action' => $this->getUrl('*/*/save', array('id' => $this->getRequest()->getParam('id'))),
            'method' => 'post'
        ));

        $fieldset = $form->addFieldset('base_fieldset', array(
            'legend' => Mage::helper('checkout')->__('Baz Information'),
            'class' => 'fieldset-wide',
        ));

        if ($model->getId()) {
            $fieldset->addField('id', 'hidden', array(
                'name' => 'id',
            ));
        }

        $fieldset->addField('name', 'text', array(
            'name' => 'name',
            'label' => Mage::helper('checkout')->__('Name'),
            'title' => Mage::helper('checkout')->__('Name'),
            'required' => true,
        ));

        $fieldset->addField('emails', 'text', array(
            'name' => 'emails',
            'label' => Mage::helper('checkout')->__('Emails'),
            'title' => Mage::helper('checkout')->__('Emails'),
            'required' => FALSE,
        ));

        $fieldset->addField('ordertype_description', 'text', array(
            'name' => 'ordertype_description',
            'label' => Mage::helper('checkout')->__('Order type description'),
            'title' => Mage::helper('checkout')->__('Order type description'),
            'required' => FALSE,
        ));

         //Load all groups and get their code and id
        foreach (Mage::getModel('customer/group')->getCollection() as $group) {
            $select[] = array('value' => $group->getCustomerGroupId(), 'label' => $group->getCustomerGroupCode());
        }

         //Add new field to the form
        $fieldset->addField('customer_group_id', 'multiselect', array(
            'label' => Mage::helper('checkout')->__('Select Customer Groupp'),
            'title' => Mage::helper('checkout')->__('Select Customer Group'),
            'name' => 'customer_group_id',
            'required' => false,
            'values' => $select
        ));



        $form->setValues($model->getData());
        $form->setUseContainer(true);
        $this->setForm($form);

        return parent::_prepareForm();
    }

}

And my actions i.e save and other are here

/www/Abc/app/code/local/Abc/Bar/controllers/Adminhtml/BazController.php
class Abc_Bar_Adminhtml_BazController extends Mage_Adminhtml_Controller_Action {

public function indexAction() {
    $this->_initAction()
            ->renderLayout();
}

public function newAction() {
    $this->_forward('edit');
}

public function editAction() {
    $this->_initAction();

    $id = $this->getRequest()->getParam('id');
    $model = Mage::getModel('abc_bar/baz');

    if ($id) {
        $model->load($id);

        if (!$model->getId()) {
            Mage::getSingleton('adminhtml/session')->addError($this->__('This baz no longer exists.'));
            $this->_redirect('*/*/');

            return;
        }
    }

    $this->_title($model->getId() ? $model->getName() : $this->__('New Baz'));

    $data = Mage::getSingleton('adminhtml/session')->getBazData(true);
    if (!empty($data)) {
        $model->setData($data);
    }

    Mage::register('abc_bar', $model);

    $this->_initAction()
            ->_addBreadcrumb($id ? $this->__('Edit Baz') : $this->__('New Baz'), $id ? $this->__('Edit Baz') : $this->__('New Baz'))
            ->_addContent($this->getLayout()->createBlock('abc_bar/adminhtml_baz_edit')->setData('action', $this->getUrl('*/*/save')))
            ->renderLayout();
}

public function saveAction() {
    if ($postData = $this->getRequest()->getPost()) {
        $model = Mage::getSingleton('abc_bar/baz');
        $model->setData($postData);

        try {
            $model->save();

            Mage::getSingleton('adminhtml/session')->addSuccess($this->__('The baz has been saved.'));
            $this->_redirect('*/*/');

            return;
        } catch (Mage_Core_Exception $e) {
            Mage::getSingleton('adminhtml/session')->addError($e->getMessage());
        } catch (Exception $e) {
            Mage::getSingleton('adminhtml/session')->addError($this->__('An error occurred while saving this baz.'));
        }

        Mage::getSingleton('adminhtml/session')->setBazData($postData);
        $this->_redirectReferer();
    }
}

public function messageAction() {
    $data = Mage::getModel('abc_bar/baz')->load($this->getRequest()->getParam('id'));
    echo $data->getContent();
}
protected function _initAction() {
    $this->loadLayout()
            // Make the active menu match the menu config nodes (without 'children' inbetween)
            ->_setActiveMenu('sales/abc_bar_baz')
            ->_title($this->__('Sales'))->_title($this->__('Baz'))
            ->_addBreadcrumb($this->__('Sales'), $this->__('Sales'))
            ->_addBreadcrumb($this->__('Baz'), $this->__('Baz'));

    return $this;
}

protected function _isAllowed() {
    return Mage::getSingleton('admin/session')->isAllowed('sales/abc_bar_baz');
}

  }

Answer 1

add this before$model->setData($postData);

$postData['customer_group_id']=implode(',',$postData['customer_group_id']);
    $model->setData($postData);

Answer 2

Solution 1:

1) change customer_group_id to varchar instead of integer

2) add this before$model->setData($postData);

$postData['customer_group_id']=implode(',',$postData['customer_group_id']);
$model->setData($postData);

Solution 2:

1) remove customer_group_id from your current table

2) make new table to store customer_group_id and your primary key of current table and store that combinatation.