Default value for empty fields in Oracle breaks default interactive enrolment (and maybe other places)

From .../lib/xmldb/classes/generators/oci8po/oci9po.class.php:

// To define the default to set for NOT NULLs CHARs without default (null=do nothing)
// Using this whitespace here because Oracle doesn't distinguish empty and null!

This means courses get a default value for the (interactive) enrolment plugin that is a white space, and not and empty string, when we use the 'Site Default' option. Later, in .../enrol/enrol.class.php we do:

function factory($enrol = '') {
global $CFG;
if (!$enrol)

So we test whether $enrol is empty or not, to use the default interactive enrolment plugin. But this breaks with Oracle, as $enrol is not empty but has a single white space character. So we end up using an enrolment plugin called ' ', which doesn't exist and generates a run-time error when we do the require_once() a few lines below.

I'd have a cursory look, and I'd say there are other places where such assuption is made (emtpy field === default value), which totally breaks when using Oracle.

(I'd like to thank Mikel Kortabarria, our local Oracle guru, for tracking down this bug .

Saludos. Iñaki.