MongoDB第一列+第二列> 2

Question

I'm trying to develop myself about mongodb. and asking some question for two days.

yesterday, I've learned that "First column > Second Column". In mongodb I've made this like:

$hg = $coll_mac->aggregate(array(
                array('$match'=>array('sezon_kodu'=>$sezon, 'tarih'=>array('$lt'=>$time))),
                array('$project'=>
                    array(
                        'c'=>array('$cmp'=>array('$ft1','$ft2'))
                    )
                ),
                array('$match'=>array('c'=>array('$gt'=>0))),
                array( '$group' => array(
                    '_id' => '',
                    'total' => array('$sum' => '$c')
                        ))
            ));

Now, how can I write this? "Select records that (First column + Second Column)>2"

Answer 1

As I said last night, you ca use $add: http://docs.mongodb.org/manual/reference/aggregation/add/

$hg = $coll_mac->aggregate(array(
    array('$match'=>array('sezon_kodu'=>$sezon, 'tarih'=>array('$lt'=>$time))),
    array('$project'=>
        array(
            'c'=>array('$add'=>array('$ft1','$ft2'))
        )
    ),
    array('$match'=>array('c'=>array('$gt'=>2))),
));