我的代码如下：

SELECT Last,OrderLine.OrdID,OrdDate,SUM(Price*Qty)  AS total_price
    FROM ((Cus INNER JOIN Orders ON Cus.CID=Orders.CID)
        INNER JOIN OrderLine
            ON Orders.OrdID=OrderLine.OrdID)
        INNER JOIN ProdFabric
            ON OrderLine.PrID=ProdFabric.PrID   
            AND OrderLine.Fabric=ProdFabric.Fabric  
    GROUP BY Last  
    ORDER BY Last DESC,OrderLine.OrdID DESC;

此代码之前已经得到了回答,但含糊不清.我想知道我哪里出错了.

You tried to execute a query that does not include the specified expression ‘OrdID’ as part of an aggregate function.

是我不断得到的错误消息,无论我改变什么,它都会给我这个错误.是的我知道,它是用SQL-92编写的,但是我该如何使它成为一个合法的功能呢？

解决方法

对于几乎每个DBMS(MySQL是我所知道的唯一例外,但也可能有其他例外),SELECT中未聚合的每一列都需要在GROUP BY子句中.在您的查询的情况下,这将是除SUM()中的列之外的所有内容：

SELECT Last,SUM(Price*Qty)  AS total_price
...   
GROUP BY Last,OrdDate  
ORDER BY Last DESC,OrderLine.OrdID DESC;