title: Magento Reports - Products - Products Ordered issue: Item (Mage_Catalog_Model_Product) with the same id already exist
body: <p>The issue:
  In Magento admin panel,  when generating report via Reports - Products - Products Ordered, an error occurs:</p>
  
  <pre>
  
      Item (Mage_Catalog_Model_Product) with the same id "45" already exist
      #0 /home/glassesm/public_html/app/code/core/Mage/Eav/Model/Entity/Collection/Abstract.php(236): Varien_Data_Collection->addItem(Object(Mage_Catalog_Model_Product))
      #1 /home/glassesm/public_html/app/code/core/Mage/Eav/Model/Entity/Collection/Abstract.php(964): Mage_Eav_Model_Entity_Collection_Abstract->addItem(Object(Mage_Catalog_Model_Product))
      #2 /home/glassesm/public_html/app/code/core/Mage/Eav/Model/Entity/Collection/Abstract.php(794): Mage_Eav_Model_Entity_Collection_Abstract->_loadEntities(false, false)
      #3 /home/glassesm/public_html/lib/Varien/Data/Collection.php(729): Mage_Eav_Model_Entity_Collection_Abstract->load()
      #4 /home/glassesm/public_html/app/code/core/Mage/Reports/Model/Totals.php(53): Varien_Data_Collection->getIterator()
      #5 /home/glassesm/public_html/app/code/core/Mage/Adminhtml/Block/Report/Grid.php(368): Mage_Reports_Model_Totals->countTotals(Object(Mage_Adminhtml_Block_Report_Product_Sold_Grid), '2011-12-10 00:0...', '2011-12-10 23:5...')
      #6 /home/glassesm/public_html/app/design/adminhtml/default/default/template/report/grid.phtml(138): Mage_Adminhtml_Block_Report_Grid->getReport('2011-12-10 00:0...', '2011-12-10 23:5...')
      #7 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(216): include('/home/glassesm/...')
      #8 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(247): Mage_Core_Block_Template->fetchView('adminhtml/defau...')
      #9 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(261): Mage_Core_Block_Template->renderView()
      #10 /home/glassesm/public_html/app/code/core/Mage/Adminhtml/Block/Template.php(81): Mage_Core_Block_Template->_toHtml()
      #11 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(758): Mage_Adminhtml_Block_Template->_toHtml()
      #12 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(525): Mage_Core_Block_Abstract->toHtml()
      #13 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(476): Mage_Core_Block_Abstract->_getChildHtml('grid', true)
      #14 /home/glassesm/public_html/app/code/core/Mage/Adminhtml/Block/Widget/Grid/Container.php(70): Mage_Core_Block_Abstract->getChildHtml('grid')
      #15 /home/glassesm/public_html/app/design/adminhtml/default/default/template/widget/grid/container.phtml(36): Mage_Adminhtml_Block_Widget_Grid_Container->getGridHtml()
      #16 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(216): include('/home/glassesm/...')
      #17 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(247): Mage_Core_Block_Template->fetchView('adminhtml/defau...')
      #18 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(261): Mage_Core_Block_Template->renderView()
      #19 /home/glassesm/public_html/app/code/core/Mage/Adminhtml/Block/Template.php(81): Mage_Core_Block_Template->_toHtml()
      #20 /home/glassesm/public_html/app/code/core/Mage/Adminhtml/Block/Widget/Container.php(295): Mage_Adminhtml_Block_Template->_toHtml()
      #21 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(758): Mage_Adminhtml_Block_Widget_Container->_toHtml()
      #22 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Text/List.php(43): Mage_Core_Block_Abstract->toHtml()
      #23 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(758): Mage_Core_Block_Text_List->_toHtml()
      #24 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(525): Mage_Core_Block_Abstract->toHtml()
      #25 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(476): Mage_Core_Block_Abstract->_getChildHtml('content', true)
      #26 /home/glassesm/public_html/app/design/adminhtml/default/default/template/page.phtml(74): Mage_Core_Block_Abstract->getChildHtml('content')
      #27 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(216): include('/home/glassesm/...')
      #28 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(247): Mage_Core_Block_Template->fetchView('adminhtml/defau...')
      #29 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Template.php(261): Mage_Core_Block_Template->renderView()
      #30 /home/glassesm/public_html/app/code/core/Mage/Adminhtml/Block/Template.php(81): Mage_Core_Block_Template->_toHtml()
      #31 /home/glassesm/public_html/app/code/core/Mage/Core/Block/Abstract.php(758): Mage_Adminhtml_Block_Template->_toHtml()
      #32 /home/glassesm/public_html/app/code/core/Mage/Core/Model/Layout.php(529): Mage_Core_Block_Abstract->toHtml()
      #33 /home/glassesm/public_html/app/code/core/Mage/Core/Controller/Varien/Action.php(389): Mage_Core_Model_Layout->getOutput()
      #34 /home/glassesm/public_html/app/code/core/Mage/Adminhtml/controllers/Report/ProductController.php(97): Mage_Core_Controller_Varien_Action->renderLayout()
      #35 /home/glassesm/public_html/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Adminhtml_Report_ProductController->soldAction()
      #36 /home/glassesm/public_html/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(253): Mage_Core_Controller_Varien_Action->dispatch('sold')
      #37 /home/glassesm/public_html/app/code/core/Mage/Core/Controller/Varien/Front.php(176): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
      #38 /home/glassesm/public_html/app/code/core/Mage/Core/Model/App.php(340): Mage_Core_Controller_Varien_Front->dispatch()
      #39 /home/glassesm/public_html/app/Mage.php(627): Mage_Core_Model_App->run(Array)
      #40 /home/glassesm/public_html/index.php(80): Mage::run('', 'store')
      #41 {main}
  
  </pre>
  
  <p>Could you help me with this issue ?</p>