How to use magento grid to display master database value

I recently ran into this problem while I was building new customer module that use admin side grid with master child releationship

then i found solution like this

At one point I need to access value customer name that in save in master table

I create a database like this

CREATE TABLE 'gallary' (

`gallary_id` int(11) unsigned NOT NULL auto_increment,

`customer_id` int(11) unsigned NOT NULL,

PRIMARY KEY (`gallary_id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Then create collection without join table it display id not master value

/app/code/local/<your interface>/<your modulename>/block/adminhtml/<modulename>/Grid.php

protected function _prepareCollection()

{

$collection = Mage::getModel('modulename/classname')->getCollection();

$this->setCollection($collection);

return parent::_prepareCollection();

}

To display customer name of customer id that we get in our collection I create one array collection that have in customer[id] and customer[name], and this is assign to  grid column  with column type= option

Like this

/app/code/local/<your interface>/<your modulename>/block/adminhtml/<modulename>/Grid.php

protected function _prepareColumns()

{
$customers= array();
$collection = Mage::getResourceModel('customer/customer_collection')
 ->addNameToSelect();
 $customers = array();
 foreach( $collection as $customer){
 $customers[] = array('value' => $customer['entity_id'], 'label'=> $customer['name']);
 }

foreach ($customers as $customer){

$customers=array($customer['value']=>$customer['label']);

}

$this->addColumn('customer', array(

'header'    =>  Mage::helper('classname')->__('Customer'),

'width'     =>  '200',

'index'     =>  'customer_id',

'type'      =>  'options',

'options'   => $customers,

));

return parent::_prepareColumns();

}

And magic is display all row  of customer column display their respective customer name.

Enjoy  magento ;