[ { $match: { director: { $ne: null }, $comment: "Stitch clientAppId=mongodb-charts-srods userId=5bf16cd1cc188900aeb5af1f" } }, { $unwind: "$genres" }, { $group: { _id: { __alias_0: "$director", __alias_1: "$genres" }, __alias_2: { $sum: 1 } } }, { $project: { _id: 0, __alias_0: "$_id.__alias_0", __alias_1: "$_id.__alias_1", __alias_2: 1 } }, { $project: { x: "$__alias_0", color: "$__alias_1", y: "$__alias_2", _id: 0 } } ]