Sql 从oracle中的子查询给定错误

我有这样的疑问：

SELECT T.custno,T.custlastname,AVG(T.OrderAmount) , T.OrderCount
FROM(
      SELECT  A.custno,A.custlastname,count(b.ordno) as OrderCount,    sum(c.qty*d.prodprice) AS  OrderAmount
  FROM customer A 
      JOIN ordertbl B ON A.custno=b.custno
      JOIN ordline C ON b.ordno=c.ordno
      JOIN  product D ON c.prodno=d.prodno
  WHERE A.custstate='CO'
  GROUP BY A.custno,A.custlastname, b.ordno) AS T
GROUP BY T.custno,T.custlastname;

我得到这个错误：

ORA-00933: SQL command not properly ended

当我显式执行内部子查询时，它运行良好。请告诉我原因

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你可以试试我猜你在外部查询的

GROUPBY

子句中缺少一列。尝试下面的查询

SELECT T.custno,T.custlastname,AVG(T.OrderAmount) , T.OrderCount
       FROM (SELECT  A.custno, 
                    A.custlastname,
                    count(b.ordno) as OrderCount,
                    sum(c.qty*d.prodprice) AS  OrderAmount
             FROM customer A 
             JOIN ordertbl B ON A.custno=b.custno
             JOIN ordline C ON b.ordno=c.ordno
             JOIN  product D ON c.prodno=d.prodno
             WHERE A.custstate='CO'
             GROUP BY A.custno,A.custlastname, b.ordno) T
       GROUP BY T.custno,T.custlastname,T.OrderCount;

试试这个：

SELECT T.custno,T.custlastname,avg(T.OrderAmount) , T.OrderCount
       FROM (SELECT  A.custno, 
                    A.custlastname,
                    count(b.ordno) as OrderCount,
                    sum(c.qty*d.prodprice) AS OrderAmount
             FROM customer A 
             JOIN ordertbl b ON A.custno=b.custno
             JOIN ordline c ON b.ordno=c.ordno
             JOIN  product d ON c.prodno=d.prodno
             WHERE A.custstate='CO'
             GROUP BY A.custno,A.custlastname,b.ordno,OrderAmount,
             OrderCount) AS T)
       GROUP BY T.custno,T.custlastname,T.OrderAmount,T.OrderCount;

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不，还是一样的结果：(