title: Aggregating and ordering over relationship properties
body: <p>I'm a Cypher newbie so I might be missing something obvious but after reading all the basic recommendation engine posts/tutorials I could find, I can't seem to be able to solve this so all help is appreciated. </p>
  
  <p>I'm trying to make a recommendation function that recommends Places to User based on Tags from previous Places she enjoyed. User have LIKES relationship to Tag which carries weight property. Places have CONTAINS relationship with Tag but Contain doesn't have any weights associated with it. Also the more Tags with LIKES weighted above certain threshold (0.85) Place has, the higher it should be ordered so this would add SUM aggregator.</p>
  
  <pre><code>(User)-[:LIKES]-&gt;(Tag)&lt;-[:CONTAINS]-(Place)
  </code></pre>
  
  <p>My problem is that I can't wrap my head around how to order Places based on the amount of Tags pointing to it that have LIKES relationship with User and then how to use LIKES weights to order Places.</p>