While unstructured "NoSQL" databases have become very popular and are the core of the HCL Domino database, there are certain circumstances which benefit from a traditional SQL database. These include:
- large and rapidly changing data sets with complex query and reporting requirements (see https://en.wikipedia.org/wiki/PostgreSQL ).
- developers that are skilled in SQL are most appropriate for business reporting needs (see https://en.wikipedia.org/wiki/SQL ).
PostgreSQL is largely considered the most reliable open source SQL database in existence. Although it is totally free, it competes regularly with commercial offerings from Oracle, Microsoft, and other vendors. Learn more at https://www.postgresql.org