Question

I’m aware that Oracle does not have a boolean type to use for parameters, and am currently taking in a NUMBER type which would have 1/0 for True/False (instead of the ‘Y’/’N’ CHAR(1) approach).

I’m not a very advanced Oracle programmer, but after doing some digging and reading some ASKTOM posts, it seems like you can restrict a field using a format for the column like:

MyBool NUMBER(1) CHECK (MyBool IN (0,1))

Is there a way to apply the same sort of a check constraint to an input parameter to a stored procedure? I’d like to restrict the possible inputs to 0 or 1, rather than checking for it explicitly after receiving the input.

Answer 1

You can use Booleans as parameters to stored procedures:

procedure p (p_bool in boolean) is...

However you cannot use Booleans in SQL, e.g. select statements:

select my_function(TRUE) from dual; -- NOT allowed

For a number parameter there is no way to declaratively add a “check constraint” to it, you would have to code some validation e.g.

procedure p (p_num in number) is
begin
   if p_num not in (0,1) then
      raise_application_error(-20001,'p_num out of range');
   end if;
   ...