Some NoSQL databases popularized the notion of “loose schema”, often misunderstood as “schemaless” — but there is always a data model in the database, the application, or the mind of the developer.
However, NoSQL schemas are designed with very different goals in mind than SQL schemas. Where SQL normalizes data, NoSQL denormalizes. Where SQL joins ad-hoc, NoSQL pre-joins. And where SQL tries to push performance to the runtime, NoSQL bakes performance into the schema. Adding to the confusion, various NoSQL databases have different ideas on what schemas should enforce.
Join Scylla’s VP Product, Tzach Livyatan, for an exploration of the core concepts of NoSQL schema design, using Scylla as an example to demonstrate the tradeoffs and rationale.