- (void) facebookFetch
{
    NSString* query = @"<my_query">;
    NSDictionary *queryParam = @{ @"q": query };
    [FBSettings setLoggingBehavior:[NSSet setWithObjects:
                              FBLoggingBehaviorFBRequests,
                              nil]];
    // Make the API request that uses FQL
    [FBRequestConnection startWithGraphPath:@"/fql"
                           parameters:queryParam
                           HTTPMethod:@"GET"
                    completionHandler:^(FBRequestConnection *connection,
                                        id result,
                                        NSError *error) {
                      if (error) {
                        NSLog(@"Error: %@", [error localizedDescription]);
                      } else {
                        NSLog(@"Result: %@", result);
                      }
                    }];

}

/** Background task **/
-(void)application:(UIApplication *)application performFetchWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
{
    NSLog(@"####### background task!");

    if (![FBSession activeSession].isOpen) {
      NSLog(@"fbsession is NOT open!");
    } else {
      NSLog(@"fbsession is open!");
      [self facebookFetch];
    }

    completionHandler(UIBackgroundFetchResultNewData);

URL:    https://graph.facebook.com//fql?sdk=ios&access_token=ACCESS_TOKEN_REMOVED&q=<my_query>&migration_bundle=fbsdk%3A20131212&format=json
Method: GET
UserAgent:  FBiOSSDK.3.13.1
MIME:   multipart/form-data; boundary=3i2ndDfv2rTHiSisAbouNdArYfORhtTPEefj3q2f

- (void) facebookFetch:(void (^)(UIBackgroundFetchResult))backgroundCompletion
{
    NSString* query = @"<my_query">;
    NSDictionary *queryParam = @{ @"q": query };
    [FBSettings setLoggingBehavior:[NSSet setWithObjects:
                              FBLoggingBehaviorFBRequests,
                              nil]];
    // Make the API request that uses FQL
    [FBRequestConnection startWithGraphPath:@"/fql"
                           parameters:queryParam
                           HTTPMethod:@"GET"
                    completionHandler:^(FBRequestConnection *connection,
                                        id result,
                                        NSError *error) {
                      if (error) {
                        NSLog(@"Error: %@", [error localizedDescription]);
                      } else {
                        NSLog(@"Result: %@", result);
                      }

                      if (backgroundCompletion) {
                          backgroundCompletion(UIBackgroundFetchResultNewData);
                      }
                    }];

}

/** Background task **/
-(void)application:(UIApplication *)application performFetchWithCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
{
    NSLog(@"####### background task!");

    if (![FBSession activeSession].isOpen) {
      NSLog(@"fbsession is NOT open!");
    } else {
      NSLog(@"fbsession is open!");
      [self facebookFetch:completionHandler];
    }