title: Spring Data JPA QueryDslPredicateExecutor find distinct results
body: <p>I have a Spring Data &amp; JPA QueryDSL based project in which I have many repository interfaces extending QueryDslPredicateExecutor like below:</p>
  
  <pre><code>public interface ProductRepository extends JpaRepository&lt;Product, Long&gt;,
      QueryDslPredicateExecutor&lt;Product&gt; {
  }
  </code></pre>
  
  <p>I am performing <code>findAll()</code> queries with <code>BooleanExpression</code>s all over my application to fetch data. However I now need to find the distinct results of a query based on a particular column.</p>
  
  <p>I am also using Projections &amp; Custom repositories in some cases to select particular columns based on <a href="https://stackoverflow.com/q/18300465/1969096">this post</a>. </p>
  
  <p>Is there a way to <code>select distinct</code> so that I only get the distinct values of a particular column for a query, based on any of the above approaches? </p>