SET @FromDate      = '2020-10-12';
SET @ToDate        = '2020-10-22';

SELECT
	5 * (DATEDIFF(@ToDate, @FromDate) DIV 7) + MID('0123455501234445012333450122234501101234000123450', 7 * WEEKDAY(@FromDate) + WEEKDAY(@ToDate) + 1, 1)

SELECT DATEDIFF(@ToDate, @FromDate) - (5 * (DATEDIFF(@ToDate, @FromDate) DIV 7) + MID('0123455501234445012333450122234501101234000123450', 7 * WEEKDAY(@FromDate) + WEEKDAY(@ToDate) + 1, 1))

SELECT fechaentrada,fechsasalida,(DATEDIFF(fechsasalida, fechaentrada)) -
        ((WEEK(fechsasalida) - WEEK(fechaentrada)) * 2) -
        (CASE WHEN weekday(fechsasalida) = 6 THEN 1 ELSE 0 END) -
        (CASE WHEN weekday(fechaentrada) = 5 THEN 1 ELSE 0 END) dia
FROM tb_opciones_copy1

fn main() {
    println!("Hello, world!");
}