Facebook FQL queries return {}

Question

Hi everyone, I'm using FQL to get data from user's stream to build a web page looks like wall-to-wall. With two queries:

query = "SELECT post_id, message, created_time FROM stream WHERE filter_key IN (SELECT filter_key FROM stream_filter WHERE uid="+user['uid']+" AND type='newsfeed') AND target_id = "+uid+" AND actor_id = "+user['uid']+" LIMIT 5"

and

query = "SELECT post_id, message, created_time FROM stream WHERE filter_key IN (SELECT filter_key FROM stream_filter WHERE uid="+user['uid']+" AND type='newsfeed') AND target_id = "+user['uid']+" AND actor_id = "+uid+" LIMIT 5"

they only return:

{}

What's wrong in my queries ? Thank you :)