Question

Given the following schema: (sorry it’s crooked)

I’m trying to get back a list of activities at a place and a count of how many play that particular activity at that place.

start root = node(0)
> match root-[:HAS_PLACE]->place-[:CAN_PLAY]->activity<-[:CAN_PLAY]-place2<-[?:PLAYS_AT]-user
> where place.Id = 1307
> return activity, count(user)
==> +---------------------------------------------------+
==> | activity                            | count(user) |
==> +---------------------------------------------------+
==> | Node[5]{Name->"Swimming",Id->5}     | 0           |
==> | Node[3]{Name->"Kick Boxing",Id->3}  | 0           |
==> | Node[12]{Name->"Basketball",Id->22} | 0           |
==> | Node[13]{Name->"Handball",Id->23}   | 0           |
==> | Node[6]{Name->"Racquetball",Id->6}  | 0           |
==> | Node[2]{Name->"Aerobics",Id->2}     | 0           |
==> +---------------------------------------------------+
==> 6 rows, 21403 ms 

While I think the above does what I want, taking 21 seconds isn’t a good thing. I believe it’s due to the optional relationship or even backtracking, but how could I make a better query?

Answer 1

try:

start root = node(0)
match root-[:HAS_PLACE]->place-[:CAN_PLAY]->activity, user-[?:PLAYS_AT]->place
where place.Id = 1307
return activity, count(user)

or use an index on the placenodes and do:

start place = node:places(Id=1307)
match place-[:CAN_PLAY]->activity, user-[?:PLAYS_AT]->place
return activity, count(user)