Merge pull request #757 from narfbg/2.1-stable

Improve CI_Upload::_file_mime_type() realiability (2.1-stable)
diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 3952d72..4dfb584 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -1387,7 +1387,21 @@
 
 		return $item.$alias;
 	}
+	
+	// --------------------------------------------------------------------
 
+	/**
+	 * Dummy method that allows Active Record class to be disabled
+	 *
+	 * This function is used extensively by every db driver.
+	 *
+	 * @access	private
+	 * @return	void
+	 */
+	protected function _reset_select()
+	{
+	
+	}
 
 }