neo4j Multiple optional paths - cypher -

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i'm tracking if user has liked , or voted on object in list of objects others posted.. can either likes , votes, not both. (a person can both , vote on object , these options not mutually exclusive).

to problem let me describe in relational terms (left joins used - object returned, liker , voter data returned if record of type exists)

[object]+ -> liker         + -> voter

what i'd return is:

objectid likerid  voterid 2343     null     88 2345     11       null 2382     44       1256 2400     null     null

yet every way i've sliced cannot come out . either row 2400 skipped (i've tried every combination of where), or values shifted likerid voterid column (bug?).

here sample of cypher:

    start objects=node(158)  match contestant-[:posted]->object_node-[:posted_object]->objects<-[?:posted_object]-object_node_a<-[?:likes]-liker     , objects<-[?:posted_object]-object_node_b<-[?:votes]-voter     return id(object, id(liker), id(voter)

it doesn't work if try id(object_node_a) = id(object_node_b)...

if try liker works.. same voter.. when try both.. bombs..

i've tried using , etc never full list of objects - either trims down list based upon matches, or gives me cartesian product distinct not resolve.

sql example: left join

i'm sql guy let me explain way - have objects table on left, , want left join liker table , voter table, , return both liker id , voter id on single row along object data. object records returned regardless if there voter or liker record.

[object]+ -> liker         + -> voter

is possible?

is possible via cypher?

hopefully haven't misunderstood. get

objectid likerid  voterid 2343     null     88 2345     11       null 2382     44       1256 2400     null     null

i.e. objects , id of liked , voted it, query should it-

start o=<lookup objects> match ul-[like?:liked]->o, uv-[vote?:voted]->o  return o,id(ul),id(uv)

this return objects no votes , likes, both votes , likes , either one. note if have multiple users voting same object likely, object row repeat each user. might want like

start o=<lookup objects> match ul-[like?:liked]->o, uv-[vote?:voted]->o  return o,collect(id(ul)),collect(id(uv))

to still row per object collection of user ids votes , likes.

to include person posted object well:

start o=node(4,5,6,7)  match ul-[like?:liked]->o, uv-[vote?:voted]->o, c-[:posted_object]->o  return o,id(ul),id(uv),id(c)

i created tiny sample play with: http://console.neo4j.org/r/in8g4w


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