In reply to RX-78:
Can't speak to the data analysis side of things because mine was software development. But my experience is that the few months of learning was enough to:
a) prove to employers that you're capable of learning this stuff quickly
b) build enough of a foundation (and confidence) to structure more learning off
c) give you enough knowledge and skills to be bordering on actually useful
With c) possibly being the least important of the three. It's getting people started in a career that's all about continuous learning regardless of your starting point anyway, not pretending that you can create a fully formed professional in a few months.