title: Issues using findAllBy method to access a list of properties on an object
body: <p>Here is the code to take a list of tags generated by params and passed into the service from the controller. I'm trying to filter the list of eateries to ONLY contain eateries with matching tag properties. I'm new to programming and grails so please forgive any silly mistakes:</p>
  
  <pre><code>    class Eatery {
          String name
          String phone
          Date lastVisited
          List&lt;Tag&gt; tags
          static hasOne = [location: Location]
          static hasMany = [tags: Tag];
          static constraints = {
              name nullable: false, blank: false
              phone nullable: true, blank: true
              location nullable: true, blank: true
              tags nullable: true, blank: true
              lastVisited nullable: true, blank: true
          }
          public String toString() {
              return name
          }
  }
  </code></pre>
  
  <p>Here is the service method: </p>
  
  <pre><code>Eatery getRandomEatery(List&lt;Tag&gt; tagList) {
      List&lt;Eatery&gt; eateryList = Eatery.findAllByTags(tagList)
      Random random = new Random()
      Integer n = eateryList.size()
      Integer selection = Math.abs(random.nextInt(n))
      Eatery eatery = eateryList.get(selection)
      return eatery
  }
  </code></pre>
  
  <p>And here is the error:</p>
  
  <pre><code> Class
  org.h2.jdbc.JdbcSQLException
  Message
  Parameter "#1" is not set; SQL statement: select this_.id as id2_0_, this_.version as version2_0_, this_.last_visited as last3_2_0_, this_.name as name2_0_, this_.phone as phone2_0_ from eatery this_ where this_.id=? [90012-164]
  Around line 16 of grails-app/services/grubspot/RandomizerService.groovy
  13://14://        }15:        List&lt;Eatery&gt; eateryList = Eatery.findAllByTags(tagList)16:        Random random = new Random()17:        Integer n = eateryList.size()18:        Integer selection = Math.abs(random.nextInt(n))19:        Eatery eatery = eateryList.get(selection)
  </code></pre>