Configure importing from a constant file and use the batch file like this:
@echo off
for %%i in (*.csv) do call :RUN_ONE %%i
goto END
:RUN_ONE
ren %%i import.csv
rem Load import.csv into SQL Server.
del import.csv
:END
For example, you may create a stored procedure that uses OPENROWSET to select data from a file:
INSERT INTO ... ( ... )
SELECT
...
FROM OPENROWSET(BULK '...import.csv',
FORMATFILE = '...import.fmt', FIRSTROW = 2)
and use sqlcmd to execute the procedure. For example:
sqlcmd -S . -E -h -1 -d Database -Q "EXEC dbo.uspImport"