问题
I want to get the full history of my wall. But I seem to hit a limit somewhere back in June.
I do multiple calls like this:
SELECT created_time,message FROM stream WHERE source_id=MY_USER_ID LIMIT 50
SELECT created_time,message FROM stream WHERE source_id=MY_USER_ID LIMIT 51,100
and so on...
But I always end up on the same last (first) post on my wall. Through facebook.com I can go back much longer so Facebook obviously have the data.
Why am I not getting older posts? Is there another way to scrape my history?
回答1:
From http://developers.facebook.com/docs/reference/fql/stream :
The stream table is limited to the last 30 days or 50 posts, whichever is greater
回答2:
I am experiencing the same thing. I don't understand it at all, but it appears that the offset cannot be greater than the limit * 1.5
Theoretically, this means that always increasing the limit to match the offset would fix it, but I haven't been able to verify this (I'm not sure whether the problems I'm seeing are other bugs in my code or if there are other limitations I don't understand about getting the stream).
Can anyone explain what I'm seeing and whatever I'm missing?
You can reproduce my results by going to the FQL Test Console:
http://developers.facebook.com/docs/reference/rest/fql.query
pasting in this query:
SELECT post_id, created_time, message, likes, comments, attachment, permalink, source_id, actor_id
FROM stream
WHERE filter_key IN
(
SELECT filter_key
FROM stream_filter
WHERE uid=me() AND type='newsfeed'
)
AND is_hidden = 0 limit 100 offset 150
When you click "Test Method" you will see one of the 2 results I am getting:
- The results come back: [{post_id:"926... (which I expected)
- It returns empty [] (which I didn't expect)
You will likely need to experiment by changing the "offset" value until you find the exact place where it breaks. Just now I found it breaks for me at 155 and 156.
Try changing both the limit and the offset and you'll see that the empty results don't occur at a particular location in the stream. Here are some examples of results I've seen:
- "...limit 50 offset 100" breaks, returning empty []
- "...limit 100 offset 50" works, returning expected results
- "...limit 50 offset 74" works
- "...limit 50 offset 75" breaks
- "...limit 20 offset 29" works
- "...limit 20 offset 30" breaks
Besides seeing the limit=offset*1.5 relationship, I really don't understand what is going on here.