Oracle选择最新的日期记录

Question

我试图找到基于日期字段的最新记录.当我在where子句中设置latest = 1时,我收到错误.请尽可能帮助.DATE是我正在排序的字段.我试过最新的= 1和最新='1'

SELECT 
STAFF_ID,
SITE_ID,
PAY_LEVEL,
ROW_NUMBER() OVER (PARTITION BY STAFF_ID ORDER BY DATE DESC) latest

 FROM OWNER.TABLE
WHERE   END_ENROLLMENT_DATE is null 
AND latest = 1

Answer 1

你不能在WHERE子句中使用select列表中的别名(因为SELECT语句的评估顺序)

你也不能OVER在WHERE子句中使用子句 - "你可以在选择列表或ORDER BY子句中使用this子句指定分析函数." (来自docs.oracle.com的引用)

select *
from (select
  staff_id, site_id, pay_level, date, 
  max(date) over (partition by staff_id) max_date
  from owner.table
  where end_enrollment_date is null
)
where date = max_date

Answer 2

假设 Staff_id + date 来自英国，这是另一种方法：

SELECT STAFF_ID, SITE_ID, PAY_LEVEL
  FROM TABLE t
  WHERE END_ENROLLMENT_DATE is null
    AND DATE = (SELECT MAX(DATE)
                  FROM TABLE
                  WHERE staff_id = t.staff_id
                    AND DATE <= SYSDATE)