Do it, do it. do it well

Even such a small but very useful function saves a lot of time:

procedure assert_equal(expected varchar2, actual varchar2) is
begin
    if expected is null and actual is not null then
         raise_application_error(-20001, 
              'Expected is null'||' Actual '||actual);
    elsif expected is not null and actual is  null then                       
         raise_application_error(-20001, 
               'Expected '||expected||' Actual is null');
    elsif  expected <>  actual then
         raise_application_error(-20001, 
               'Expected '||expected||' Actual '||actual);
    end if;
end;