GET parameters duplicating pageviews (1 reply)

Dashboard->Pages shows a list of visited pages. We have some parameters that were not excluded since the beginning of time, so they're counting as multiple pages, even though its the same one.

Example:
http://my.page.com/page2.php?nid=7584
http://my.page.com/page2.php?nid=7745
http://my.page.com/page2.php?nid=8765

Now we just set up 'nid' to be excluded, but PIWIK is only excluding it from this point onwards. I need to find a way to do this retroactively as we'll certainly run into this issue in the future.

Is there a way to do this through PIWIK instead of trying to update the database tables on our own?

Thanks