cypher query get wrong results

1
votes

I have a graph which contains 3 types of nodes : Post, User, Cat, every cat have so many posts that are linked together with a 'next' relationship, every user can comment on these posts and the comment is a 'Commented' relationship with a 'content' and 'id' property.
I want to get the posts of some cat and all the comments related to every post.
I've tried this but it don't give me posts without comments:

MATCH (cat:Cat {id:1})-[:lastPost]->(last)-[:next*0..]->(rest)
MATCH (rest)<-[c:Commented]-(u:User)
RETURN c, rest

Is there any way to achieve what I want in Cypher ? thank you

1
neo4jcypher

1 Answers

2
votes

Try changing the second MATCH statement to an OPTIONAL MATCH:

MATCH (cat:Cat {id:1})-[:lastPost]->(last)-[:next*0..]->(rest)
OPTIONAL MATCH (rest)<-[c:Commented]-(u:User)
RETURN c, rest

Any values that don't match the OPTIONAL MATCH pattern will be NULL.