用先前的行值更新行 [英] update row with previous rows value

问题描述

我有变量Table

i have variable Table

declare @Table Table
(
Value1 float,
Value2 float,
Total float
)
Insert into @Table values (1,1)
Insert into @Table values (2,2)
Insert into @Table values (3,3)
Insert into @Table values (4,4)
Insert into @Table values (5,5)

我需要总列为当前行+上一行的总和(value1 + value2)


所以结果会像这样

Value1个值总计
---------------------
1 1 2
2 2 6
3 3 12
4 4 20
5 5 30

所以我怎么计算总数
我不想使用循环，因为在实际示例中，我大约有2000行或更多行，因此我使用任何循环语句都将花费太多时间
我需要保持良好的性能

[代码]阻止更新了

i need the total column to be the sum(value1+value2) from the current row +Previous Rows


so the result ''ll be like that

Value1 Values Total
---------------------
1 1 2
2 2 6
3 3 12
4 4 20
5 5 30

so how i can calculate the total
i don''t want to use loop because in the real example i have about 2000 rows or more so of i use any loop statement it ''ll took too much time
i need to keep the performance good

[code] block updated

推荐答案

尝试以下操作:
在SQL Server中计算简单运行总计 [ ^ ]

希望这会有所帮助，
巴勃罗.

Try this:
Calculating simple running totals in SQL Server[^]

Hope this helps,
Pablo.

create trigger trig_product
on table
after insert
as 
declare @input varchar(25)
set @input = (select distinct    max(Total)  from  table)
update  table
	set  Total = @input 
	from  table where ID=(select max(ID) from Table)

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