Mongoose unwind
An example solution would $unwind and $group the elements back but in a different way. For example:
db.getCollection('orders').aggregate([ // Unwind on "orderItems". {$unwind: '$orderItems'}, {$group: { // Group by "orderItems.productDispatchStatus". _id: {_id: '$_id', productDispatchStatus: '$orderItems.productDispatchStatus'}, orderItems: {$push: '$orderItems'}, // Add all other fields. orderStatus: {$first: '$orderStatus'}, orderNumber: {$first: '$orderNumber'} }}, {$project: { // Map "_id" back to the original. _id: '$_id._id', // Add all other fields. orderStatus: 1, orderItems: 1, orderNumber: 1 }}])