mongoose - MongoDB Query Based on ObjectId Reference Condition -

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मेरे पास MongoDB संग्रह बिल्लियों है जिसके पास एक ObjectId संदर्भ फ़ील्ड है zooId संग्रह चिड़ियाघर ।

मैं कैसे की तरह कुछ पूछताछ के बारे में जाना होगा

db.Cats.find ({zooId.zooName: 'San डिएगो '}) गिनती ()

जहां क्वेरी की स्थिति zooName में zooId संदर्भ में है? < / P>

मैं मोंगोज का उपयोग करके समझता हूं, मैं कुछ संदर्भों को वास्तव में लाने के लिए populate विधि को कॉल कर सकता हूं, लेकिन मैं मोंगॉड कंसोल या रोबोमोंगो में सीधे कैसे इसी तरह की बातें करूँगा?

धन्यवाद!

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सरल कोडिंग: 

  var cats = 0; Db.Zoo.find ({zooName: 'San Diego'}) .पूर्व (फ़ंक्शन (zooItem) {var id = zooItem._id; cats + = db.Cat.find ({'zooId': id})। गणना ( );}); प्रिंट (बिल्लियों);

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