db={"User":[{"catagory":[{"name":"test","createdAt":"2024-02-01T21:47:34.215Z","_id":"65bc1176cfb7da6997273ae3","cards":[{"_id":"65c43a9539206da4c953e334","createdAt":"2024-02-08T02:21:09.344Z","updatedAt":"2024-02-08T02:21:09.344Z","__v":0},{"_id":"65c43a9539206da4c953e32e","createdAt":"2024-02-08T02:21:09.344Z","updatedAt":"2024-02-08T02:21:09.344Z","__v":0},{"_id":"65c43a9539206da4c953e332","createdAt":"2024-02-08T02:21:09.344Z","updatedAt":"2024-02-08T02:21:09.344Z","__v":0},{"_id":"65d2447cbad1f058de61ecca","createdAt":"2024-02-18T17:55:08.414Z","updatedAt":"2024-02-18T17:55:08.414Z","__v":0}]},{"name":"baseball","createdAt":"2024-02-01T23:12:46.996Z","_id":"65bc256ecfb7da6997273c71","cards":[]}]}],"cards":[{"_id":"65c43a9539206da4c953e334","title":"PSA 9 1996 Topps Finest Gold w/ Coating #269 Kobe Bryant Rookie Card","date":"2023-11-16T05:00:00.000Z","price":125000,"image":"s-l300.webp","search":[],"createdAt":"2024-02-08T02:21:09.344Z","updatedAt":"2024-02-08T02:21:09.344Z","__v":0},{"_id":"65c43a9539206da4c953e32e","title":"1996-97 Topps Finest Bronze Refractor #74 Kobe Bryant (RC) PSA 7 W/ Coating","date":"2024-02-01T05:00:00.000Z","price":130000,"image":"s-l300.webp","search":[],"createdAt":"2024-02-08T02:21:09.344Z","updatedAt":"2024-02-08T02:21:09.344Z","__v":0},{"_id":"65c43a9539206da4c953e332","title":"1996-97 Fleer Ultra Series 2 Basketball Factory Sealed Hobby Box-Kobe Bryant RC?","date":"2023-11-28T05:00:00.000Z","price":124999,"image":"s-l300.webp","search":[],"createdAt":"2024-02-08T02:21:09.344Z","updatedAt":"2024-02-08T02:21:09.344Z","__v":0},{"_id":"65d2447cbad1f058de61ecca","title":"HUGE SPORTS CARD COLLECTION! 2023 CJ Stroud Justin Herbert Rookie Auto RPA READ","date":"2024-02-17T05:00:00.000Z","price":75000,"image":"s-l300.webp","search":[],"createdAt":"2024-02-18T17:55:08.414Z","updatedAt":"2024-02-18T17:55:08.414Z","__v":0}]}

db.User.aggregate([{$unwind:{path:"$catagory",preserveNullAndEmptyArrays:true}},{$unwind:{path:"$catagory.cards",preserveNullAndEmptyArrays:true}},{$lookup:{from:"cards",localField:"catagory.cards._id",foreignField:"_id",as:"catagory.cards"}},{$group:{_id:"$catagory._id",userId:{$first:"$_id"},categoryId:{$first:"$catagory._id"},name:{$first:"$catagory.name"},createdAt:{$first:"$catagory.createdAt"},cards:{$push:{$arrayElemAt:["$catagory.cards",0]}}}},{$group:{_id:"$userId",catagory:{$addToSet:{_id:"$categoryId",name:"$name",createdAt:"$createdAt",cards:"$cards"}}}}])