Database
[{_id:ObjectId("633cdd1ab47cdac0ab830428"),url:"https://www.example.com/1"},{_id:ObjectId("633cdd54b47cdac0ab830429"),url:"https://www.example.com/2",isChecked:true},{_id:ObjectId("633cdd89b47cdac0ab83042a"),url:"https://www.example.com/3"}]
Query
db.collection.find({$or:[{isChecked:false},{isChecked:{$exists:false}}]})