通过别名列访问SQL查询ORDER

Question

我对一个简单的sql查询有疑问。

这是我在Access 2013中的查询：

SELECT Shippers.Shipper_ID, Shippers.ShipperName, SUM(Orders.TotalPrice) AS TotPr FROM Orders
LEFT JOIN Shippers
ON Orders.Shipper_ID=Shippers.Shipper_ID
GROUP BY Shippers.Shipper_ID, Shippers.ShipperName
ORDER BY Shippers.ShipperName;

...而且效果很好。 但是，如何将别名列（TotPr）放在ORDER BY中呢？

谢谢你的帮助 ：）

Answer 1

您可以使用以下公式：

SELECT Shippers.Shipper_ID, Shippers.ShipperName, SUM(Orders.TotalPrice) AS TotPr
FROM Orders LEFT JOIN
     Shippers
     ON Orders.Shipper_ID=Shippers.Shipper_ID
GROUP BY Shippers.Shipper_ID, Shippers.ShipperName
ORDER BY Shippers.ShipperName, SUM(Orders.TotalPrice);

Answer 2

使用SUM(Orders.TotalPrice)而不是别名，您需要聚合

因此您的查询将是：

SELECT Shippers.Shipper_ID, Shippers.ShipperName, SUM(Orders.TotalPrice) AS TotPr
FROM Orders LEFT JOIN
     Shippers
     ON Orders.Shipper_ID=Shippers.Shipper_ID
GROUP BY Shippers.Shipper_ID, Shippers.ShipperName
ORDER BY Shippers.ShipperName, SUM(Orders.TotalPrice);

Answer 3

由于大多数引擎在内部计算SQL的方式，Order By通常不喜欢计算列。 尝试这个：

SELECT Shipper_ID, ShipperName, TotPr
FROM
(SELECT Shippers.Shipper_ID, Shippers.ShipperName, SUM(Orders.TotalPrice) AS TotPr FROM Orders
LEFT JOIN Shippers
ON Orders.Shipper_ID=Shippers.Shipper_ID
GROUP BY Shippers.Shipper_ID, Shippers.ShipperName) ShipQuery
ORDER BY ShipQuery.ShipperName, ShipQuery.TotPr;

（免责声明：我没有对此进行测试。）