如何执行多查询 fql 语句？

Question

从下面的 FQL 查询中，我可以获取我的新闻源中包含“www.youtube.com”的帖子的 actor_id 和附件数据。但是，我还希望能够获得该用户的图片和姓名。我如何将其合并到以下查询中？

SELECT created_time, post_id, actor_id, type, updated_time, attachment
FROM stream 
WHERE post_id IN 
   (SELECT post_id
    FROM stream
    WHERE ('video') IN attachment 
    AND source_id IN
       (SELECT uid2
        FROM friend
        WHERE uid1=me())
    LIMIT 100)

编辑：

    #right fql query, but prints only part of it
    posts_query = "SELECT created_time, post_id, actor_id, type, updated_time, attachment FROM stream WHERE post_id in (select post_id from stream where ('video') in attachment AND source_id IN ( SELECT uid2 FROM friend WHERE uid1=me()) limit 100)"
    fql_var = "https://api.facebook.com/method/fql.query?access_token=" + token['access_token'] + "&query=" + posts_query + "&format=json"
    data = urllib.urlopen(fql_var)
    fb_stream = json.loads(data.read())
    #print ast.literal_eval(json.dumps(fb_stream))

    users_query = "SELECT uid, first_name FROM user WHERE uid IN (SELECT actor_id FROM (" + posts_query+"))"
    fqlquery_user = "https://api.facebook.com/method/fql.query?access_token=" + token['access_token'] + "&query=" + users_query + "&format=json"
    user_data2 = urllib.urlopen(fqlquery_user)
    user_stream2 = json.loads(user_data2.read())
    print ast.literal_eval(json.dumps(user_stream2))

Answer 1

看来你不能只用一个查询来做到这一点，因为：

1. 在 FQL 中，您一次只能从一个表中 SELECT。
2. FQL 中没有 JOIN。 （见this question和that one）

如果可以的话，它会是这样的：

SELECT created_time, post_id, actor_id, type, updated_time, attachment, user.first_name
FROM stream
WHERE ('video') in attachment AND 
        source_id IN (SELECT uid2 FROM friend WHERE uid1=me())
LEFT JOIN user ON user.uid=actor_id
LIMIT 100

但是没有连接，所以你需要使用 Facebook 所谓的multiquery，你会有两个查询：

posts_query =
SELECT created_time, post_id, actor_id, type, updated_time, attachment
FROM stream
WHERE ('video') in attachment AND 
        source_id IN (SELECT uid2 FROM friend WHERE uid1=me())
LIMIT 100

users_query =
SELECT uid, first_name
FROM user
WHERE uid IN (SELECT actor_id FROM #posts_query)

这是Explorer 的链接供您测试。

注意：您在原始查询中做了一些无用的操作，即从表中进行选择，并在同一个表的 where 子句中添加子查询。所以这是多余的。

更新：

#right fql query, but prints only part of it
posts_query = "SELECT created_time, post_id, actor_id, type, updated_time, attachment FROM stream WHERE post_id in (select post_id from stream where ('video') in attachment AND source_id IN ( SELECT uid2 FROM friend WHERE uid1=me()) limit 100)"
users_query = "SELECT uid, first_name FROM user WHERE uid IN (SELECT actor_id FROM (#posts_query))"

queries = {'posts_query': posts_query, 'users_query': users_query}
fql_var = "https://api.facebook.com/method/fql.query?access_token=" + token['access_token'] + "&q=" + json.dumps(queries_json) + "&format=json"
data = urllib.urlopen(fql_var)
fb_stream = json.loads(data.read())
print ast.literal_eval(json.dumps(fb_stream))

我们的想法是发送两个查询，将其名称作为键，以 JSON 编码，以便 Facebook 了解 #posts_query 是您在同一个 API 请求中发送的那个。您发送的名称与您在 JSON 编码对象中发送的名称完全相同，而不是用查询本身替换它。查看关于 multiquery 的文档以获取详细信息和示例。

Answer 2

您需要使用FQL Multiquery，这样您就有两个查询——您自己的来获取“帖子”，另一个来获取“演员”。查询是一起执行的，您必须调整代码以将使用 actor_id 的值返回的两个数组配对。

"posts":"your_query_here"
"actors":"SELECT name,pic_square FROM user WHERE uid IN (SELECT actor_id FROM #posts)"

You can see the results of this query here