MongoDB Query Based on ObjectId Reference Condition
Simple coding:
var cats = 0;db.Zoo.find({zooName: 'San Diego'}).forEach(function(zooItem){ var id = zooItem._id; cats += db.Cat.find({'zooId' : id}).count();});print(cats);
Simple coding:
var cats = 0;db.Zoo.find({zooName: 'San Diego'}).forEach(function(zooItem){ var id = zooItem._id; cats += db.Cat.find({'zooId' : id}).count();});print(cats);