NoSQL databases differ from relational databases by allowing more complex structures without requiring traditional relationships such as one-to-many or one-to-one. Instead, NoSQL databases leverage flexible types, such as arrays or subdocuments, to store related data efficiently within a single document. This flexibility enables developers to design models that suit their application’s querying and performance needs.

Jakarta NoSQL is a Java framework that simplifies interactions with NoSQL databases, including MongoDB. It provides annotations that determine how data is mapped and stored, allowing developers to control whether embedded objects are grouped or stored in a flat manner.