Today I came across something an APEX developer does not see very often, a very rare species of error. Although there certainly have been sightings before, this one was caught on tape! Behold, the infamous ORA-NNNNN, straight from the belly of Salesforce!
The Problem
It turns out this error can occur when trying to store Attachments (with APEX), without enabling Attachments on the (custom) object. With ORA-20001: ORA-06512 as a result.
The Solution
Enable Attachments on the SObject in question.