About 30 years ago...
A friend was setting up the IT for a mid-size financial company. He used a database tool to configure the initial data structure, and then put the tool away. He then wrote his own C code to take it from there. It's just data on the disk; It's not that complicated.
For Amazon's case, it wouldn't be difficult to home brew a database tool that's better than Oracle. Perhaps they could even begin to market their database technology, competing with Oracle.
Then, perhaps Oracle could start selling things (e.g. books) online. They could get Amazon to help with setting up the required databases.
Biting the hand that feeds IT
