Cypher Neo4j query -

i developing kind of social trivia game main db neo4j. having hard time in specific use-case.

i have challenge node 2 opponents nodes related:

(opponent1)-[:opponent]->(challenge)<-[:opponent]-(opponent2) 

the challenge relate subject node:

challenge-[:subject]->subject 

each subject relate many questions:

subject-[:has]->question 

if opponent answered specific question before bellow relation exist:

opponent-[:answer]->question 

the use-case: need retrieve x questions (which never been answered both opponents) challenge

i have following cypher query:

start challenge=node({0}) , subject=node({1})  match (opponent1)-[:opponent]->(challenge)<-[:opponent]-(opponent2)  opponent1,opponent2,subject match (subject)-[:has]->(question)   length(opponent1-[:answer]->question) = 0 , length(opponent2-[:answer]->question) = 0  return question limit {2} 

the above query works fine , retrieve possible questions challenge.

the problem questions retrieved consequently , not randomly.

explanation: each question related template node has category property.

question-[:template]->template 

the questions created in first place template mean questions specific category has sequenced id in db therefore above query retrieves questions same category.

i want able retrieve challenge questions randomly. also, query structure correct performance perspective?

i'm not aware of native way of how random result, there smting asked here: neo4j: there way/how select random nodes?

about query, depends on data, try rather this:

start challenge=node({0}) , subject=node({1}) match (opponent1)-[:opponent]->(challenge)<-[:opponent]-(opponent2) opponent1,opponent2,subject match (subject)-[:has]->(question) not(opponent1-[:answer]->question) , not (opponent2-[:answer]->question) return question limit {2}