Sokil\Mongo\Pipeline\GroupStage::first PHP Method

GroupStage Class Documentation Show file Open project: sokil/php-mongo

first() public method

Returns the value that results from applying an expression to the first document in a group of documents that share the same group by key. Only meaningful when documents are in a defined order.

See link: http://docs.mongodb.org/manual/reference/operator/aggregation/first

public first ( string $field, literal \| callable \| Sokil\Mongo\Pipeline\Expression $expression ) : GroupStage
$field	string
$expression	literal \| callable \| Sokil\Mongo\Pipeline\Expression	Expression
return	GroupStage

    public function first($field, $expression)
    {
        $this->stage[$field]['$first'] = Expression::normalize($expression);
        return $this;
    }

GroupStage

addToSet

avg

first

last

max

min

push

setId

sum

toArray