DataTable.php

		foreach($array as $label => $row)
		{
			// we make sure that the label column is first in the list! 
			// important for the UI javascript mainly...
			// array_merge doesn't work here as it reindex the numeric value
			// see the test testMergeArray in PHP_Related.test.php
			$cleanRow[Piwik_DataTable_Row::COLUMNS] = array('label' => $label) + $row;
			if(!is_null($subtablePerLabel)
				// some rows of this table don't have subtables 
				// (for examplecase of the campaign without keywords )
				&& isset($subtablePerLabel[$label]) 
			)
			{
				$cleanRow[Piwik_DataTable_Row::DATATABLE_ASSOCIATED] = $subtablePerLabel[$label];
			}
			$this->addRow( new Piwik_DataTable_Row($cleanRow) );
		}
	}

	/**
	 * At destruction we try to free memory
	 * But php doesn't give us much control on this
	 */
	public function __destruct()
	{
		unset($this->rows);
	}
	
}