The simplest statement is the NULL statement. This statement is an executable statement that does nothing.

NULL;

The following is the simplest possible valid SPL program:

BEGIN
    NULL;
END;

The NULL statement can act as a placeholder where an executable statement is required such as in a branch of an IF-THEN-ELSE statement. For example:

CREATE OR REPLACE PROCEDURE divide_it (
    p_numerator     IN  NUMBER,
    p_denominator   IN  NUMBER,
    p_result        OUT NUMBER
)
IS
BEGIN
    IF p_denominator = 0 THEN
        NULL;
    ELSE
        p_result := p_numerator / p_denominator;
    END IF;
END;