From which country did you taste the most ~distinct~ beers?
db.beer.aggregate( [
{ '$group' : {
'_id' : '$brewery_country',
'beers' : { '$addToSet' : '$beer_name' },
} },
*{ '$unwind' : '$beers' },*
] ).pretty()
Result:
{ "_id" : "Portugal", "beers" : "Cheers Sem álcool" }
…
{ "_id" : "Portugal", "beers" : "Super Bock Preta Sem Alcool" }
…
{ "_id" : "Canada", "beers" : "CID Rosé" }
…
{ "_id" : "Canada", "beers" : "Revenante" }