[{"_id":1,"category":"fruit","userId":1,"name":"Banana"},{"_id":2,"category":"fruit","userId":2,"name":"Apple"},{"_id":3,"category":"fresh-food","userId":1,"name":"Fish"},{"_id":13,"category":"fresh-food","userId":1,"name":"Fish"},{"_id":113,"category":"fresh-food","userId":1,"name":"Fish"},{"_id":1113,"category":"fresh-food","userId":1,"name":"Fish"},{"_id":11113,"category":"fresh-food","userId":1,"name":"Fish"},{"_id":4,"category":"fresh-food","userId":2,"name":"Shrimp"},{"_id":5,"category":"vegetable","userId":1,"name":"Salad"},{"_id":6,"category":"vegetable","userId":2,"name":"carrot"}]

db.collection.aggregate([{"$match":{}},{"$group":{"_id":{"name":"$name"},"data":{"$push":"$$ROOT"}}},{"$project":{"_id":0,"name":"$_id.name","videos":{"$slice":["$data",1]}}}])