Sql ORA-00979:不是orderdetails的GROUP BY表达式

此sql语句有什么问题，我不断遇到以下错误：

SQL错误：ORA-00979:不是GROUP BY表达式 97900000-不是表达式的分组 *原因： *行动：

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如果我有另一个变量，比如Shipped

SELECT orderdetails.orderid, orderdate, NVL2(Shippeddate, "Not Shipped" , "Shipped" ) as "Shipped" ,sum (quantity *( unitprice - unitprice * discount))as "Order Total" FROM orderdetails
INNER JOIN orders orders on orderdetails.orderid = orders.orderid
WHERE customerid = 'ERNSH'
GROUP BY orderdetails.orderid , orderdate, Shipped
ORDER BY "Order Total" desc;

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将orderdate添加到GROUP BY子句：

select orderdetails.orderid,
    orderdate,
    sum(quantity * (unitprice - unitprice * discount)) as "Order Total"
from orderdetails
inner join orders orders on orderdetails.orderid = orders.orderid
where customerid = 'ERNSH'
group by orderdetails.orderid, orderdate
order by "Order Total" desc;

或者，如果列不应位于group by子句中，则对该列使用聚合函数：

select orderdetails.orderid,
    max(orderdate) as orderdate,   ---  see which function is suitable
    sum(quantity * (unitprice - unitprice * discount)) as "Order Total"
from orderdetails
inner join orders orders on orderdetails.orderid = orders.orderid
where customerid = 'ERNSH'
group by orderdetails.orderid
order by "Order Total" desc;

以上两个在语法上是正确的，但在逻辑上你必须做出决定

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此外，如果可能的话，尝试使用较小的别名来干净地编写查询，并使用别名/表名一致地限定列名。

将orderdate添加到GROUP BY子句GROUP BY ORDERDDETAILS.orderid，orderdate将表订单别名为orders的任何原因？唯一可能的用法是，您可以通过名称顺序而不是名称顺序来引用它。我看不出有什么意义……为什么我们必须在group by子句中包含orderdate，而不必包含订单总额？与group by orderdetails.orderid、orderdate、Order TotalGroup by子句类似，group by子句必须在SELECT子句中包含所有非聚合列/表达式。订单总数是聚合的结果。因此，不存在于组中。这正是为什么我不需要在第二个查询的group by子句中包含orderdate的原因，因为我们在该列上使用了聚合函数。如果我有另一个变量，如SHIFED？？选择orderdetails.orderid，orderdate，NVL2Shippeddate，Not Shipped，Shipped as Shipped，sum quantity*unitprice-unitprice*Deffantas Order Total FROM orderdetails内部联接orders orders on orderdetails.orderid=orderid，其中customerid='ERNSH'按orderdetails分组。orderid，orderdate，按订单总描述发货；

select orderdetails.orderid,
    max(orderdate) as orderdate,   ---  see which function is suitable
    sum(quantity * (unitprice - unitprice * discount)) as "Order Total"
from orderdetails
inner join orders orders on orderdetails.orderid = orders.orderid
where customerid = 'ERNSH'
group by orderdetails.orderid
order by "Order Total" desc;