sql - count(*) ではなく min() 関数に対して Oracle で group by を使用する

Question

3 列に group by を使用する方法 group by 式ではないというエラーが表示されます。これがクエリです。

select
   brewer.name as brewer,beer.name as beer,count(ratings.score) as LowestRating
from ratings,beer,brewer
where ratings.beer=beer.id and beer.brewer=brewer.id
group by brewer,beer; 

Answer 1

GROUP BYテーブル全体ではなく、列ごとに行う必要があります。

select
     brewer.name as brewer,
     beer.name as beer,
     count(ratings.score) as LowestRating
  from
    ratings,
    beer,
    brewer
where
  ratings.beer = beer.id
  and beer.brewer = brewer.id
group by brewer.name, beer.name;