计算每个学生的分数。两列的计算相互依赖

Question

我想使用 cte 或任何其他方法计算 sql 服务器中的剩余点数

计算公式：见附图。总分 100 我已经使用 cte 为每个学生使用了行计数。

Row_no  |st_id  |plenty |weekBonus  |weekbenformula |remaining_Points
1       |1      |5      |0          |0              |95
2       |1      |3      |2          |2              |94
3       |1      |2      |0          |0              |92
4       |1      |3      |2          |6              |95
5       |1      |1      |1          |1              |95
6       |1      |3      |1          |1              |93
7       |1      |2      |0          |0              |91

Excel附上示例图片。

第一行计算 st_id 1: 100 -5 +0= 95

st_id1 的第二行计算：95 - 3 +2=94 这里我必须取之前剩余的点数。等等...

或此问题的任何其他解决方案。

Answer 1

这可以通过递归 cte 来完成，如下所示。 weekbenformula & remaining_points 的计算是按照公式

declare @tbl table
(
    row_no            int,
    st_id             int,
    plenty            int,
    weekbonus         int,
    weekbenformula    int,
    remaining_points  int
)

insert into @tbl (row_no, st_id, plenty, weekbonus)
values  (1, 1, 5, 0),
        (2, 1, 3, 2),
        (3, 1, 2, 0),
        (4, 1, 3, 2),
        (5, 1, 1, 1),
        (6, 1, 3, 1),
        (7, 1, 2, 0);

with rcte as
(
    select  row_no, st_id, plenty, weekbonus,
            weekbenformula = 0,
            remaining_points = 95
    from    @tbl
    where   row_no  = 1

    union all

    select  t.row_no, t.st_id, t.plenty, t.weekbonus,
            weekbenformula   = case when r.remaining_points >= 95 then 1 else 3 end 
                             * t.weekbonus,
            remaining_points = r.remaining_points - t.plenty
                             + (case when r.remaining_points >= 95 then 1 else 3 end * t.weekbonus)
    from    rcte r
            inner join @tbl t   on  r.row_no    = t.row_no - 1
)
select  *
from    rcte

db<>fiddle demo

计算每个学生的分数。两列的计算相互依赖

calculation of points for each student. two columns' calculations are based each other

sql

sql-server

stored-procedures

function

common-table-expression