如何返回具有最新日期的行？

Question

我的查询返回如下数据：

$percent_complete

但是，我真的只关心获得Type A，B和C的最新数据。这样我的回报会是这样的：

ID |    ProcessID   | Type| Value | Date
--------------------------------------------------
1  |        2       | A   |  10   | 2/23/2016 10:10:42 AM
1  |        2       | B   |  20   | 2/23/2016 10:10:42 AM
1  |        2       | C   |  30   | 2/23/2016 10:10:42 AM
1  |        1       | A   |  11   | 1/6/2016 12:48:04 PM
1  |        1       | B   |  21   | 1/6/2016 12:48:04 PM
1  |        1       | C   |  31   | 1/6/2016 12:48:04 PM
2  |        4       | A   |  10   | 7/21/2016 11:28:22 AM
2  |        4       | B   |  20   | 7/21/2016 11:28:22 AM
2  |        4       | C   |  30   | 7/21/2016 11:28:22 AM
2  |        3       | A   |  11   | 6/21/2016 09:41:07 AM
2  |        3       | B   |  21   | 6/21/2016 09:41:07 AM
2  |        3       | C   |  31   | 6/21/2016 09:41:07 AM

我尝试在select子句中使用max，但这不起作用。

这是我的sql，仅限于示例一个“ID”，以及实际返回的示例：

ID |    ProcessID   | Type| Value | Date
--------------------------------------------------
1  |        2       | A   |  10   | 2/23/2016 10:10:42 AM
1  |        2       | B   |  20   | 2/23/2016 10:10:42 AM
1  |        2       | C   |  30   | 2/23/2016 10:10:42 AM
2  |        4       | A   |  10   | 7/21/2016 11:28:22 AM
2  |        4       | B   |  20   | 7/21/2016 11:28:22 AM
2  |        4       | C   |  30   | 7/21/2016 11:28:22 AM

返回：

select f.folderrsn,fpi.processrsn,fpi.infocode, fpi.infovalue, fp.enddate
from folderprocessinfo fpi
join folderprocess fp on fp.processrsn = fpi.processrsn
join folder f on f.folderrsn = fp.folderrsn
where fpi.infocode in (51437,51438,51439)
and trunc(f.issuedate) > '01-JAN-16'  
and not fpi.infovalue is null
and f.folderrsn = 11179547 --limited to one "ID" for example
order by fp.enddate asc

Answer 1

您可以使用O(m)：

row_number()