[hodgesrm]

OLTP databases are optimized for mutable data. OLAP databases are optimized for immutable data. There's a big difference between appropriate data structures for each use case that has little to do with hardware capabilities.

OLAP databases tend to write columns in large blocks and apply sort orders to improve compression. This type of structure works well if you write the data once and read it many times. It's horrendously inefficient for concurrent updates to things like user session contexts. (Or even reading them for that matter.) You are better off using a row store with ACID transactions and relatively small pages.

The dichotomy has been visible for decades and shows no sign of disappearing, because the difference is mostly how you arrange and access data, not so much the hardware used.