Joining two collection / tables

Question

I have situation I want to join two tables having some data related to orders.One table contain order id as increment_id and other table contain order id as order_id.I am joining the tables through customer_id.Now the thing is when we display the column in backend grid we define some column name to it.But now I have two columns containing different names.Then how I can use data of both the column together and can give name to grid column. Till now my join code is

$collection = Mage::getModel('creditlog/creditlog')->getCollection();
 $collection->addFieldToFilter('main_table.customer_id', $this->getRequest()->getParam('id'));
 $logTable = Mage::getSingleton('core/resource')->getTableName('creditlog/logdata');
 $collection->getSelect()->join(array('a'=> $logTable),
 'main_table.customer_id = a.customer_id', array('order_id','credit_amount','date','status'));

And my grid column is

$this->addColumn('increment_id', array(
 'header' => Mage::helper('creditlog')->__('Your orders'),
 'index' => 'increment_id',
 'type' => 'text',
 )
 );

Please help.

• Qaisar Satti: your can use 'renderer' => 'Spacename_Modulename_Block_Adminhtml_Action', to show that data if it is about displaying data in one column. `
• Vivek Khandelwal: can you guide me using union instead of join?
• Qaisar Satti: sorry i don't get get it is about not join working? or about showing the result in grid?
• Vivek Khandelwal: Join is working fine but the result not of use.As it will result in two column with different name so how will show them in grid.?
• Qaisar Satti: you want to show column value in same column or two different column?

Answer 1

$this->addColumn('increment_id', array(
 'header' => Mage::helper('creditlog')->__('Your orders'),
 'index' => 'increment_id',
 'renderer' => 'Spacename_Modulename_Block_Adminhtml_Action',
 )
 );

and your renderer block

 class Spacename_Moduelename_Block_Adminhtml_Action extends Mage_Adminhtml_Block_Widget_Grid_Column_Renderer_Abstract
{
 public function render(Varien_Object $row)
 {
 return $row->getIncrementId().''. $row->getOrderId();
 }
}