couchdb - CouchDB - SQL Group by に似た Map Reduce

Question

CouchDB に保存されている次のサンプル ドキュメントを検討してください

 {
"_id":....,
"rev":....,
"type":"orders",
"Period":"2013-01",
"Region":"East",
"Category":"Stationary",
"Product":"Pen",
"Rate":1,
"Qty":10,
"Amount":10
}

{
"_id":....,
"rev":....,
"type":"orders",
"Period":"2013-02",
"Region":"South",
"Category":"Food",
"Product":"Biscuit",
"Rate":7,
"Qty":5,
"Amount":35
}

次の SQL クエリを検討してください

SELECT Period, Region,Category, Product, Min(Rate),Max(Rate),Count(Rate), Sum(Qty),Sum(Amount)
FROM Sales
GROUP BY Period,Region,Category, Product;

上記のSQLクエリと同等のcouchdbでマップ/リデュースビューを作成し、次のような出力を生成することは可能ですか?

[
    {
        "Period":"2013-01",
        "Region":"East",
        "Category":"Stationary",
        "Product":"Pen",
        "MinRate":1,
        "MaxRate":2,
        "OrdersCount":20,
        "TotQty":1000,
        "Amount":1750
    },
    {
    ... 
    }

]