public function filterBySport($sport, $comparison = null)
    {
        if ($sport instanceof \gossi\trixionary\model\Sport) {
            return $this
                ->addUsingAlias(SkillTableMap::COL_SPORT_ID, $sport->getId(), $comparison);
        } elseif ($sport instanceof ObjectCollection) {
            if (null === $comparison) {
                $comparison = Criteria::IN;
            }

            return $this
                ->addUsingAlias(SkillTableMap::COL_SPORT_ID, $sport->toKeyValue('PrimaryKey', 'Id'), $comparison);
        } else {
            throw new PropelException('filterBySport() only accepts arguments of type \gossi\trixionary\model\Sport or Collection');
        }
    }