title: A method to detect non-repetition relation when neo4j is inserted?
body: <p>My steps:</p>
  <ol>
  <li><p>Read CSV to create node A</p>
  </li>
  <li><p>Make relational mapping with node B in Neo4j library</p>
  </li>
  <li><p>Read new CSV to add node A</p>
  </li>
  <li><p>Do relational mapping with node B in the library</p>
  </li>
  </ol>
  <p>So there's a new relationship repetition problem, how can we detect if it's repeated, and if it's repeated then we don't associate it</p>
  <p><a href="https://i.stack.imgur.com/FQ0Mg.png" rel="nofollow noreferrer">enter image description here</a></p>
  <p>My version is neo4j 3</p>