Not strictly a job title - but when I worked for a large public utility I was part of the team that moved our data from 'flat' files to a more modern database system.
My (rather unworldly) boss said in a meeting "We need to have a snappy name for this system" ...
... I replied (to widespread smirking) "Well the old system was MasterFile, so why not call this MasterBase?"
To my horror, he just nodded and said "Great, that's settled then"
So, from that point on, we were The Masterbase Team ...