MongoDB - automatically maintain data integrity

Question

I am interested in migrating from a relational database to MongoDB for better performance. I would save redundant, denormalized data in several places, and I wonder if it is possible to automatically maintain data integrity WITHOUT application code.

For example, if I have a user document ...

User: { _id: "...", userName: "johndoe", displayName: "John Doe", TotalTasks: 3 }

And then the task document ...

Task: { _id "...", title: "Finish Reports", userID: "...", userName: "johndoe", userDiplayName: "John Doe" }

How can I automatically ensure that username and displayName remain unchanged in the relevant documents? How can I guarantee that TotalTasks will be updated when new tasks are added or removed for this user?

Answer 1

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Answer 2

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