SQL - グループ化された結果の中にユニークな値を探す

Question

Iている以下の表

**Order** 
- Id (int) 
- OrderDate (datetime) 
- OrderNumber (nvarchar) 
- CustomerId (int) 
- TotalAmount (decimal) 

 

**OrderItem** 
- Id (int) 
- OrderId (int) 
- ProductId (int) 
- UnitPrice (decimal) 
- Quantity (int) 

 

**Product** 
- Id (int) 
- ProductName (nvarchar) 
- SupplierId (int) 
- UnitPrice (decimal) 
- Package (nvarchar) 
- IsDiscontinued (bit) 

 

**Supplier** 
- Id (int) 
- CompanyName (nvarchar) 
- ContactName (nvarchar) 
- ContactTitle (nvarchar) 
- City (nvarchar) 
- Country (nvarchar) 
- Phone (nvarchar) 
- Fax (nvarchar) 

私は単一の国から供給される製品を含むすべての注文を調べる必要があります。どんな助けもありがたい。

Answer 1

それは

select * from (
     select * from (
      select ROW_NUMBER() over(partition by s.Country order by s.Country) RowNo,o.* from [order] as o 
      inner join OrderItem as oi on o.Id = oi.OrderId 
      inner join Product as p on ProductId = p.Id 
      inner join Supplier as s on p.SupplierId = s.Id 
     ) as t 
     where RowNo > 1 
    ) as t 
    right join [order] as o on t.Id = o.Id 
    where t.Id is null