How to write a query to find those documents that has array of objects and all those objects has same keys with some value in mongodb

I want to get all the documents that has an array of objects with all its array elements containing the key with value as null { “_id” : ObjectId(“5d769272db4f632399abbb14”), “used”:true, “contacts”:[ {email:null, username:”john”}, {email:”steve@gmail.com”,username:”steve245″} ] }, { “_id” : ObjectId(“5d769272db4f632399abbb14”), “used”:false, “contacts”:[ {email:null, username:”paul”}, {email:null, username:”retinza612″} ] } result to retrieved { “_id” : ObjectId(“5d769272db4f632399abbb14”),…

Joining data from multiple files using aggregate gives ‘cyclic dependency error’-Mongoose/MongoDB

I’ve 3 tables 1.User _id:123 name email 2.contact: userId:123 hospitalId:321 3.Hospital: _id:321 I need mongoose equivalent of below SQL query: select *from user where _id in (select userId from contact where hospitalId = 321) Users.aggregate( [ { “$match”: { “_id”: { “$in”: db.contact.distinct(“userid”,{ “hospitalId”: 321 }) } }} ]) when I tried this I got…

How to fix ‘The method MongoClient is undefined’ error in java using mongodb java drivers for CRUD method

I am trying to connect my java code with mongodb locally hosted. Using dependencies – jUnit v3.8.1 and mongodb-driver-sync v3.11.0. But getting a error while establishing the connection using method “MongoClient” undefined method. Tried creating a new method for “MongoClient” but there is nothing to create over there. public static void main(String[] args) { MongoClient…