In Mongoose How to exclude documents that have common value in particular field but return first document only?
You can use $group for grouping same values, and $replaceRoot for replace grouped documents from $group.
db.collection.aggregate([ // updated match/where conditions { $match: { isRead: false, isChat: true, receiverBy: userId } }, { $group: { _id: "$createdBy", root: { $first: "$$ROOT" } } }, { $replaceRoot: { newRoot: "$root" } }])Working Playground: https://mongoplayground.net/p/qzyXuP-3nv8