Q:

Counting relationships size in Neo4j

I have a Neo4j Graph database which stores Twitter data.
Each Tweet is about a Topic and has got this kind of relationship:
(t:Tweet)-[:ABOUT]->(t1:Topic)

A User can be mentioned by a Tweet due to this relationship
(t:Tweet)-[:MENTIONS]->(u:User) 
I'd like to know how many users are mentioned in tweets regarding a specific topic.
My query is:
match (n:Topic)<--()-[r:MENTIONS]->(u:User) 
where n.name='politics'
return count(r)

Is this query right? Because I've got unexpected results.
Thanks a lot.

A:

You can try using the following query.
match (n:Topic{name:'politics'}) 
RETURN size((n)<--()-[:MENTIONS]->(:User)) as count

