SPRING CONCEPTS
MongoDB
Spring Concepts / MongoDB
MongoDB stores BSON documents in collections inside databases.
Understand the idea
A todo document has fields such as _id, title, and completed. Spring Data maps Java objects to those documents. Collections do not require relational @Entity mappings or JDBC SQL. A single-document write is atomic; a separate read and save can still encounter competing edits.
A concrete example
{
"_id": "generated identifier",
"title": "Teach Spring",
"completed": false
}In the application
The three labs use separate databases: todo_mvc, todo_rest, and todo_personal.
A document database still needs schema decisions, validation, indexes, and access controls.