join query laravel with condition code example

Example 1: laravel + join 2 eloquent queries

$select->joinSub(
                    $selectSubQry,
                    'ag',
                    'ag.id',
                    '=',
                    'agp.userId'
                );

Example 2: laravel outer join

->join('answers as answers', 'responses.answer_id', '=', 'answers.id', 'left outer')