Question

我有两个表，根据要求我们需要减去下面给出的值。请帮助我解决这个难题....

Table1
MONTH   Fee(Advance) 
APRIL   5000 


Table2  
MONTH   Fee 
MAY     2000 
JUNE    300 
JULY    1800 
AUG     1200 
Sep     1500 



Expecting Result 
ROW 1   MAY     5000(TABLE1.ADVANCE)-2000(TABLE2.FEE)=   3000
ROW 2   JUNE    3000-300                             =   2700
ROW 3   JULY    2700-1800                            =   900
ROW 4   AUG     900-1200                             =   -300
ROW 5   Sep     -300-1500                            =   -1800

Answer 1

我不确定这是否是正确的做法。而不是SQL语句，也许存储过程会有帮助吗？

DECLARE @AdvanceFee INT;
DECLARE @cnt INT = 1;
DECLARE @cnt_total INT = (Select Count(MONTH) From Table2);

SET @AdvanceFee = (Select Fee(Advance) from Table1)

WHILE @cnt <= @cnt_total 
BEGIN 

    Select MONTH, @AdvanceFee = @AdvanceFee - Fee 
    FROM Table2
    WHERE ROW_NUMBER = @cnt

    SET @cnt = @cnt + 1;

END

Answer 2

您需要一个包含月份名称和数字的表格（'MAY'= 5，'Sep'= 9，...）。然后使用SUM OVER获取总计：

select
  t.month,
  (select fee from table1 where month = 'APRIL') - sum(t.fee) over (order by m.monthnum)
    as balance
from table2 t
join months m on m.name = t.month
order by m.monthnum;

减去sql中的值

2 个答案: