Question

我在这里开始提问（Query to get the most recent record and with the higher value），但我有一个小的变更请求。

我将有一个包含Percentage的列和另一个包含Char的列，以指示它是值还是百分比。

我正在尝试做这样的事情：

select  card,
                         service,
                         max(date),
                         case when type = 'v'
                         then
                         MAX(value) KEEP (
                            dense_rank first order by date desc
                        )
                         else 
                         max(percentage) valor keep (
                           dense_rank first order by date desc
                         ) end   
                 from table
                 group by card,
                 service;

但我得到了ORA-00979：不是GROUP BY表达式。

Answer 1

您尚未提及列type是否因给定card,service对而异。假设它是相同的，您应该能够使用嵌套的select获得结果，包括内部type和select中的group by。

 SELECT card
    ,service
    ,CASE 
        WHEN type = 'v'
            THEN value
        ELSE perc
        END AS max_result
FROM (
    SELECT card
        ,service
        ,type
        ,MAX(date_t) AS Date_t
        ,MAX(value) KEEP (
            DENSE_RANK FIRST ORDER BY date_t DESC
            ) AS value
        ,MAX(percentage) KEEP (
            DENSE_RANK FIRST ORDER BY date_t DESC
            ) AS perc
    FROM yourtable
    GROUP BY card
        ,service
        ,type
    );

Demo

查询以获得卡和服务的最新记录和（如果是关系）更高的值或百分比

1 个答案: