Neo4j / Cypher密集节点匹配结果排序

Question

I have a (:User) dense node with following relationships:

(:User)-[:SUBSCRIBED]->(:User)
(:User)-[:CONNECTED]->(:SocialNetwork)

If I execute query below

MATCH (u:User {UserId:id})
MATCH (u)-[:SUBSCRIBED]->(s)
RETURN s

I get user's subscribers ordered by recent which is expected.

But the same query with additional matching pattern brakes this ordering

MATCH (u:User {UserId:id})
MATCH (u)-[:SUBSCRIBED]->(s)
OPTIONAL MATCH (s)-[:CONNECTED]->(sn)
RETURN s, COUNT(sn.FriendCount)

Could someone explain why ordering by recent doesn't work in the second example.

Answer 1

There is no guarantee of order in your query because you don't have an ORDER clause, run the same query 1000 times and I'm sure the order will change at some point.

You should order at the end of the query :

MATCH (u:User {UserId:id})
MATCH (u)-[:SUBSCRIBED]->(s)
OPTIONAL MATCH (s)-[:CONNECTED]->(sn)
RETURN s, COUNT(sn.FriendCount)
ORDER BY s.time // ? property representing the time