我正在使用NorthWind SQL数据库。对于不熟悉的人,它具有一些下表:
Orders,
OrderDetails,
Products,
categories
(Orders.OrderID = OrderDetails.OrderID)
(Products.ProductID = OrderDetails.ProductID)
(Categories.categoryID = Products.categoryID)
Orders has a column named "OrderDate" (formatted as dd/mm/yy)
OrderDetails has a column named "Price"
我需要显示每年的总“收入”。即,所有“价格”之和。知道怎么做吗?
最佳答案
请尝试这样的操作,因为我们没有完整的表结构。这种GROUP BY用于MySQL
SELECT SUM (OD.Price) AS Revenue FROM OrderDetails OD
INNER JOIN Orders O ON Orders.OrderID = OrderDetails.OrderID
GROUP BY YEAR(O.OrderDate);
关于mysql - 显示每年的收入,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/29396763/