"ORA-00923: FROM keyword not found where expected" 在我的预言机查询中遇到

Question

      SELECT TITLE, CONCAT(TO_CHAR(SUM((COST-RETAIL)/COST)*100), '100'), '%') 
      AS "Markup"
      FROM BOOKS
      GROUP BY TITLE; 

::目标::
我正在计算我的产品(书)的利润率。

::泽的问题::
当我尝试运行所述SQL时，得到错误

ORA-00923: FROM关键字未找到

我提前感谢你对我的问题的任何和所有的意见。

Answer 1

你的括号不平衡，我左数4右数5。此错误通常发生在格式错误导致无法到达FROM子句时(缺少/额外的逗号，不平衡的括号等)

Answer 2

  SELECT TITLE, TO_CHAR( SUM( COST-RETAIL )/ SUM( COST )) || '%'
      AS "Markup"
      FROM BOOKS
      GROUP BY TITLE; 

Answer 3

有一个额外的右括号，它应该是这样的

SELECT TITLE, CONCAT(TO_CHAR(SUM((COST-RETAIL/COST)*100), '100'), '%') 
AS "Markup"
FROM BOOKS
GROUP BY TITLE;