/// Implement the logic for query 1, return trace of the results.
Implement the logic for query 1, return trace of the results.
Implement the logic for query 1 return trace of the results .
fn query_1<G, Submission, Person, Date>(
    comms: &Collection<G, (Submission,Date,String,Person,Submission)>,
    posts: &Collection<G, (Submission,Date,String,Person)>,
    likes: &Collection<G, (Person, Submission)>,
    probe: &mut ProbeHandle<G::Timestamp>,
) -> TraceAgent<OrdKeySpine<String, G::Timestamp, isize>>
where
    G: Scope,               // timely dataflow scope
    G::Timestamp: Lattice,  // differential dataflow timestamp constraint
    Submission: ExchangeData+std::hash::Hash+std::fmt::Display,
    Person: ExchangeData+std::hash::Hash,
    Date: ExchangeData+std::hash::Hash,
{
    use differential_dataflow::operators::reduce::Threshold;
    use differential_dataflow::operators::join::Join;
    use differential_dataflow::operators::arrange::arrangement::ArrangeBySelf;
    use timely::dataflow::operators::probe::Probe;
    let comms_parents = comms.map(|(id, _, _, _, parent)| (parent, id));
    let direct_replies = posts
        .map(|(pid, _, _, _)| (pid.clone(), ()))  // extract post ids
        .join_map(&comms_parents,
                  |post_id, _dummy, comm_id| (post_id.clone(), comm_id.clone())
        )  // -> (post_id, comment_id)
        ;
    let all_replies = direct_replies
        .iterate(|transitive| {
            let comms_parents = comms_parents.enter(&transitive.scope());
            let direct_replies = direct_replies.enter(&transitive.scope());
            return transitive
                .map(|(post_id, comment_id)| (comment_id.clone(), post_id.clone()))
                .join_map(&comms_parents,
                         |_parent_comment, post_id, child_comment| (post_id.clone(), child_comment.clone())
                )
                .concat(&direct_replies)
                .distinct()
                ;
        }) // -> (post_id, reply_id)
       ;
    let liked_comments =
    likes
        .distinct() // Remove duplicate likes (maybe not necessary?)
        .map(|(_user,comm)| (comm, ()))
        .join_map(
            &all_replies.map(|(post_id, comment_id)| (comment_id, post_id)),
            |_comment_id, _dummy, post_id| post_id.clone()
        )
        ;
    let comms_theyselves = all_replies.explode(|(post_id, _comment_id)| Some((post_id, 10)));
    use differential_dataflow::trace::implementations::ord::OrdValSpine;
    use differential_dataflow::operators::reduce::ReduceCore;
    let post_score = 
    posts
        .map(|post| post.0)         // ensure all posts get a score.
        .concat(&liked_comments)    // likes contribute to posts.
        .concat(&comms_theyselves)  // comments contribute to posts.
        .arrange_by_self()
        .reduce_abelian::<_,OrdValSpine<_,_,_,_>>("count", |_k,s,t| t.push((s[0].1.clone(), 1)))
        .join_map(
            &posts.map(|post| (post.0, post.1.clone())), 
            |post, count, ts| (post.clone(), (*count-1,ts.clone())),
        );
    let arrangement = 
    limit(&post_score, 3)
        .map(|vec| format!("{}|{}|{}", vec[0], vec[1], vec[2]))
        .arrange_by_self();
    arrangement.stream.probe_with(probe);
    arrangement.trace
}
fn query_1 < G , Submission , Person , Date > ( comms : & Collection < G , ( Submission , Date , String , Person , Submission ) > , posts : & Collection < G , ( Submission , Date , String , Person ) > , likes : & Collection < G , ( Person , Submission ) > , probe : & mut ProbeHandle < G :: Timestamp > , ) -> TraceAgent < OrdKeySpine < String , G :: Timestamp , isize > > where G : Scope , // timely dataflow scope G :: Timestamp : Lattice , // differential dataflow timestamp constraint Submission : ExchangeData + std :: hash :: Hash + std :: fmt :: Display , Person : ExchangeData + std :: hash :: Hash , Date : ExchangeData + std :: hash :: Hash , { use differential_dataflow :: operators :: reduce :: Threshold ; use differential_dataflow :: operators :: join :: Join ; use differential_dataflow :: operators :: arrange :: arrangement :: ArrangeBySelf ; use timely :: dataflow :: operators :: probe :: Probe ; let comms_parents = comms . map ( | ( id , _ , _ , _ , parent ) | ( parent , id ) ) ; let direct_replies = posts . map ( | ( pid , _ , _ , _ ) | ( pid . clone ( ) , ( ) ) ) // extract post ids . join_map ( & comms_parents , | post_id , _dummy , comm_id | ( post_id . clone ( ) , comm_id . clone ( ) ) ) // -> (post_id, comment_id) ; let all_replies = direct_replies . iterate ( | transitive | { let comms_parents = comms_parents . enter ( & transitive . scope ( ) ) ; let direct_replies = direct_replies . enter ( & transitive . scope ( ) ) ; return transitive . map ( | ( post_id , comment_id ) | ( comment_id . clone ( ) , post_id . clone ( ) ) ) . join_map ( & comms_parents , | _parent_comment , post_id , child_comment | ( post_id . clone ( ) , child_comment . clone ( ) ) ) . concat ( & direct_replies ) . distinct ( ) ; } ) // -> (post_id, reply_id) ; let liked_comments = likes . distinct ( ) // Remove duplicate likes (maybe not necessary?) . map ( | ( _user , comm ) | ( comm , ( ) ) ) . join_map ( & all_replies . map ( | ( post_id , comment_id ) | ( comment_id , post_id ) ) , | _comment_id , _dummy , post_id | post_id . clone ( ) ) ; let comms_theyselves = all_replies . explode ( | ( post_id , _comment_id ) | Some ( ( post_id , 10 ) ) ) ; use differential_dataflow :: trace :: implementations :: ord :: OrdValSpine ; use differential_dataflow :: operators :: reduce :: ReduceCore ; let post_score = posts . map ( | post | post . 0 ) // ensure all posts get a score. . concat ( & liked_comments ) // likes contribute to posts. . concat ( & comms_theyselves ) // comments contribute to posts. . arrange_by_self ( ) . reduce_abelian :: < _ , OrdValSpine < _ , _ , _ , _ > > ( " " , | _k , s , t | t . push ( ( s [ 0 ] . 1 . clone ( ) , 1 ) ) ) . join_map ( & posts . map ( | post | ( post . 0 , post . 1 . clone ( ) ) ) , | post , count , ts | ( post . clone ( ) , ( * count - 1 , ts . clone ( ) ) ) , ) ; let arrangement = limit ( & post_score , 3 ) . map ( | vec | format ! ( " " vec [ 0 ] vec [ 1 ] vec [ 2 ] ) ) . arrange_by_self ( ) ; arrangement . stream . probe_with ( probe ) ; arrangement . trace }
Implement the logic for query 1, return trace of the results.
Implement the logic for query 1 return trace of the results .
comms
&Collection<G, (Submission,Date,String,Person,Submission)>
posts
&Collection<G, (Submission,Date,String,Person)>
likes
&Collection<G, (Person, Submission)>
probe
&mut ProbeHandle<G::Timestamp>