如何在Sqlplus中對結果進行分組Oracle

Question

我想顯示BookTitle，Firstname和COUNT of Copies。當我運行查詢時，它會給出一個錯誤說明分組。但是當我將它分組時，並不表示分組。有人能幫我嗎？

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

刪除您group by語句，然後添加這個，

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

假設你所有的那裏的條件是正確的，你知道自己在做什麼。