基于前一天的索引周末

我有一个查询，其选择语句如下所示：

SELECT 
    CAST(p.date AS DATE) AS 'Date', 
    x.Month,
    x.Version,
    x.Value AS 'fcst',
     CASE WHEN isholiday = 0 
     THEN ROW_NUMBER() OVER (PARTITION BY x.Department, x.Month, p.isholiday ORDER BY p.date)
     ELSE 0
     END AS 'Index'

输出如下：

 Date       Month   Version fcst    isholiday   Index
2020-01-01  January 3plus9  3679    1            0
2020-01-02  January 3plus9  3679    0            1
2020-01-03  January 3plus9  3679    0            2
2020-01-04  January 3plus9  3679    1            0
2020-01-05  January 3plus9  3679    1            0
2020-01-06  January 3plus9  3679    0            3
2020-01-07  January 3plus9  3679    0            4
2020-01-08  January 3plus9  3679    0            5
2020-01-09  January 3plus9  3679    0            6
2020-01-10  January 3plus9  3679    0            7
2020-01-11  January 3plus9  3679    1            0
2020-01-12  January 3plus9  3679    1            0
2020-01-13  January 3plus9  3679    0            8
2020-01-14  January 3plus9  3679    0            9
2020-01-15  January 3plus9  3679    0            10
2020-01-16  January 3plus9  3679    0            11
2020-01-17  January 3plus9  3679    0            12
2020-01-18  January 3plus9  3679    1            0
2020-01-19  January 3plus9  3679    1            0
2020-01-20  January 3plus9  3679    0            13

索引列基于“ isHoliday”列。如case语句所示，在isHoliday = 1的每个点，索引显示0。相反，如果天<> 1，则我需要Index值显示为其上方的Index值。

例如，在日期= 1月4日和1月5日的行上，索引需要显示为2。我试图对case语句进行更改，但无法找到解决方案。