/**
  * Gets the master query.
  *
  * @returns xfCriterion
  */
 public function getMaster()
 {
     if (count($this->queries) != 1) {
         throw new xfParserException('A boolean query is still open.');
     }
     return $this->master->optimize();
 }
 /**
  * @see xfCriterion
  */
 public function optimize()
 {
     $this->criterion->optimize();
     return $this;
 }