I am trying to find the distinct user IDs on comments to a post. I know this can be done with SQL with the DISTINCT clause, but I am not sure how it might be done with fql. If there is not any way, what would be one approach to doing so, assuming I pull down all the fromid on a post_id?
FQL isn't like SQL in the sense that you don't get duplicates for the same reasons SQL does (JOINs, etc.), so no, there's no DISTINCT keyword that I know of. If you're having an issue parsing a specific query, you should post that so we can help further.