Question

试图让这个查询解决，但我似乎无法找出错误。有帮助吗？

select s.IDENTIFIERS,
       s.store_id,
       ifnull(d.SALES_PRICE,ifnull(u.SALES_PRICE,s.SALES_PRICE)) as SALES_PRICE
       from BOOK_SALES as s
       LEFT OUTER JOIN store AS BV 
                    ON bv.store_id = s.store_id 
   left outer join discount as d
                on d.IDENTIFIERS=s.IDENTIFIERS
               and d.from_date<=s.sales_date
               and d.to_date>=s.sales_date
               and u.to_date<0>
   left outer join discount as u
                on u.IDENTIFIERS=s.IDENTIFIERS
               and u.to_date=0

Answer 1

试试这个：

select s.IDENTIFIERS,
       s.store_id,
       isnull(d.SALES_PRICE,isnull(u.SALES_PRICE,s.SALES_PRICE)) as SALES_PRICE
       from BOOK_SALES as s
       LEFT OUTER JOIN store AS BV 
                    ON bv.store_id = s.store_id 
   left outer join discount as d
                on d.IDENTIFIERS=s.IDENTIFIERS
               and d.from_date<=s.sales_date
               and d.to_date>=s.sales_date
               and d.to_date='12/12/1989'
   left outer join discount as u
                on u.IDENTIFIERS=s.IDENTIFIERS
               and u.to_date='12/12/1989'

IFNULL用于My-sql，不在sql server中，请点击此链接null function in database

怎么了？ 'ifnull'不是公认的内置函数名称

1 个答案: