Steven, If I am understanding you correctly, perhaps you would be a bit more explicit: where does "latest update number" get set? I suspect you mean that the install code is looking for functions with signatures like "mymodule_update_42"; you are saying that if there is a "mymodule_update_41", but no number higher than "42", then the update number will be "42". I am asking this because if this behavior is documented, the documentation is well hidden, and for the record, I'd like somebody to point to where this is documented, so that others can actually find it in future. Rob Steven Wittens wrote:
* I've noticed that there are calls in install.inc to register schema versions, but I haven't seen any examples of their being used. How *should* those functions be used?
You shouldn't.
Hook_install is invoked when a module is enabled for the first time. Right before that, the schema version is set to the latest update number in install.inc (or 0 if there are none).
Then later, when updates are added, update.php will pick them up and autoselect the right version. So the first update should start with version 1.be
Steven Wittens