小编use*_*749的帖子

有谁知道为什么我无法TotalSales在此查询中进行分组,如果是,我该如何解决此问题:

select coalesce(Author_ID, 'All Authors') as Author_ID
, case when Author_ID  is null then ' ' else coalesce(Book_ID, 'All Books') end as Book_ID
, TotalQuantity  
, coalesce(TotalSales, 'No Sales') as TotalSales   
from (    
     select  author_id as Author_ID 
            , book_id as Book_ID
            ,  sum(quantity) as TotalQuantity  
            ,  sum(quantity * order_price) as TotalSales   
            from a_bkinfo.book_authors   
            join a_bkorders.order_details using (book_id)
            where author_sequence = 1           
            group by Author_id, Book_ID, TotalSales with rollup
     ) tbl;

当作者没有图书销售时,我想在TotalSales下包含"无销售".这是更新版本.我不肯定它是正确的,但我确实有输出,似乎解决了这个问题.这里是:

select coalesce(Author_ID, 'All Authors') as Author_ID
, …