The point is that the relational model is a fully general purpose mathematical model for managing data with integrity and with ad hock access. Most other model

The point is that the relational model is a fully general purpose mathematical model for managing data with integrity and with ad hock access. Most other models are for high performance of specific access paths and punt integrity management to code, which is a throwback to the 70s. They’re glorified file systems and data structure caches. Mongo has a reputation for losing your data. There are cases where scale and availability kills you and you need something like Cassandra or whatnot. But there are few as flexible and general as Oracle or Postgres.