After Delete from your table just execute below script it will re arrange your ID
CREATE PROCEDURE INSERTID_FDA_UNII_SUBSET
AS
BEGIN
Declare @ID int
Declare @MaxID int
Declare @OtherVal nvarchar(20)
DECLARE UserDet_cursor CURSOR FOR
SELECT Id,Uniicode FROM Table1
open UserDet_cursor
Set @MaxID = 1
FETCH NEXT FROM UserDet_cursor into @ID,@OtherVal
while @@FETCH_STATUS =0
BEGIN
update Table1 set ID = @MaxID where OtherVal= @OtherVal and ID = @ID
FETCH NEXT FROM UserDet_cursor into @ID,@OtherVal
END
CLOSE UserDet_cursor
DEALLOCATE UserDet_cursor
END