添加文本文件中具有相同ID的值

Question

我想知道是否有一个Windows命令可以添加两个不同的值，这些值在文件中具有相同的ID。

例如：

文件：

id;value
01;25
02;12
01;2
03;21
03;-5

结果：

id;value
01;27 /* 25 + 2 */
02;12
03;16 /* 21 - 5 */

Answer 1

对于需要答案的人，我找到了一种方法：

setlocal EnableDelayedExpansion
echo off
rem write header in output file
echo id;value> output.csv
rem remove the header of the file and loop
for /f "tokens=1,2 delims=;" %%A in ('more +1 my_file.csv') do (
    set "result="
    rem search if current id is in the temp list (tmp file) of processed ids
    for /f "delims=" %%i in ('findstr /c:"%%A;" output.csv') do set result=!result!%%i
    rem if the id is not in tmp file (the id is not yet processed)
    if "!result!"=="" (
        set sum=0
        rem get all values related to the current id and calculate the sum 
        for /f "tokens=2 delims=;" %%V in ('findstr /c:"%%A;" my_file.csv') do (
            set /a sum+=%%V
        )
        echo %%A;!sum!>> output.csv
    )
)