In MongoDB version 2.4, there are Aggregat() and Pineline() pipeline queries, but how to use this function in version 2.0.6, because 2.0.6 does not have the aggregate method. So how to implement aggregation group query? Need to use group() method.
PHP中文网2017-05-02 09:25:07
Aggregation is a new feature added in 2.2. Consider using map/reduce in earlier versions.
