存储过程占用过多的执行时间。有没有办法优化以下的sql脚本

Question

我想从Marks Column驱动获得的标记，总标记和平均列，这是varchar类型。

我写的存储过程花了很多时间执行。由于表包含346599条记录。存储过程有3个更新quires init。

Declare @Max_ROWss int
Declare @j int
Declare @Marks_Obtained int
Declare @Total_Marks int
Declare @Marks nvarchar(50)
Declare @Average int

Set @MAx_ROWss = (Select Count([Row Number]) From [dbo].[Drv Tevta 3 Full] ) -- Max([Row Number]) will also work
Set @j = 1
while (@j<= @MAx_ROWss)
Begin
    set @Marks = (select [Marks] from [dbo].[Drv Tevta 3 Full] where [Row Number] = @j)

    Set @Total_Marks =cast((select SUBSTRING(@Marks, CHARINDEX('/', @Marks) + 1, 10)) as int)
    set @Marks_Obtained = CAST((Select SUBSTRING(@Marks,0,CHARINDEX('/',@Marks))) as int)

    Update [dbo].[Drv Tevta 3 Full] 
    set [Marked Obtained] = @Marks_Obtained
    where [Row Number] = @j

    Update [dbo].[Drv Tevta 3 Full] 
    set [Total Marks] = @Total_Marks
    where [Row Number] = @j

    set @Average = ((@Marks_Obtained*100)/@Total_Marks)
    Update [dbo].[Drv Tevta 3 Full] 
    set [Average] = @Average
    where [Row Number] = @j

    set @j = @j + 1
End

有没有更好的方法可以做到？或者我只需要等待！

Answer 1

您不需要Map<String,Map<String,Object>> map = list.stream() .collect(Collectors.toMap(m -> m.keySet().iterator().next(), Function.identity())); 循环来执行此操作

while