如何在 Sqlplus Oracle 中对结果进行分组

Question

我想显示书名、名字以及 COUNT 份。当我运行查询时，它给出了一个错误，说要分组。但是当我分组时，它说不是分组的表达。有人可以帮我吗？

SELECT bk.BookTitle, au.FirstName, COUNT(bkc.BookCopyID), rb.ReservedDate 
FROM Book bk, Book_Author ba, BookCopy bkc, ReserveBook rb, Author au 
WHERE 
    bkc.BookID = bk.BookID 
    AND ba.BookID = bkc.BookID 
    AND ba.AuthorID = au.AuthorID 
    AND bkc.BookCopyID = rb.BookCopyID 
    AND rb.ReservedDate >= trunc(trunc(sysdate,'MON')-1,'MON') 
    AND rb.ReservedDate < trunc(sysdate,'MON') 
GROUP BY bkc.BookCopyID;

Answer 1

删除你的 group by 声明并添加这个，

Group by bk.BookTitle,au.FirstName,rb.ReservedDate

假设您的所有 where 条件都正确并且您知道自己在做什么。