Neo4j gem - Create relationship between two nodes only if it doesn't exist

Question

If I have two nodes ( self ) and friend_node , what's the most efficient way to do this check if I already know my two nodes.

I built this off of what you taught me last time but this seems convoluted given that I know where my nodes are. Is there anything easier?

self.query_as(:user).match(friend: {uuid: friend_node.id}).where("NOT(user-[:friends_with]->(friend:User))").pluck(:friend) unless friend_node.blank?

Answer 1

假设用户上有一个名为friends的关联，那么user.friends.include?(friend_node)就是这样。