What is your most tasted style?
Logical Approach:
*group* by style and add *count*
*sort* by *count* descendingly
Pipeline:
db.beer.aggregate( [
{ '$group' : { '_id' : '$beer_type', 'count' : { '$sum': 1 } } },
{ '$sort' : { 'count' : -1 } },
] ).pretty()
Pipeline (in 3.4):
db.beer.aggregate( [
{ *'$sortByCount'* : '$beer_type' },
] ).pretty()
Result:
{ "_id" : "Cider", "count" : 730 }
{ "_id" : "English Bitter", "count" : 164 }
{ "_id" : "Stout", "count" : 139 }
{ "_id" : "English Pale Ale", "count" : 135 }
…