WordPress – get_permalink

Hello to all.

I have a little problem with a query, I’m selecting the posts you have derterminati requirements through a simple select:

mysql_query("SELECT post_id FROM wp_postmeta WHERE meta_key='pianta' and meta_value = like '%parola_da_cercare%' ");

Everything is working correctly … after using a while loop I do return different url with the function:
get_parmalink($id_post);

What happens: that if a post I edited it in the results gives me the same post in a number equal to the number of changes made??, with url like nuovo_id-revision-id_post_originale.

Any suggestions to exclude these urls?
Also because it does not work, gives error 404.

Thank you.