javascript - How to query for objects stored in an array in a mongoDB -

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i have following nested object stored in mongodb:

var appointment = new schema ({      students: [{user1:string,user2:string, _id: false}], });

i want query appointments studentname stored in array students either in user1 or user2. have no idea how achieve that? if array use:

    appointment.find({         students: {$in: [studentname]}     }, function(err, appointmentsdb) {         //     });

you can use $or operator , dot notation this:

appointment.find({ $or: [     { 'students.user1': studentname },     { 'students.user2': studentname } ]}, callback);

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