[{"clubName":"test","staff":["62bbe47f8fececa06b9187d8","624f4b56ab4f5170570cdba3"/**IDS of staff members*/],},{"clubName":"test1","staff":["62bbe47f8fececa06b9187d8","624f4b56ab4f5170570cdba4"/**IDS of staff members*/],}]

db.collection.aggregate([{"$unwind":"$staff"},{"$group":{"_id":"null","ids":{"$addToSet":"$staff"}}},{"$project":{"_id":0,}},{$skip:0},{$limit:10}])