You are previewing MongoDB in Action.

MongoDB in Action

Cover of MongoDB in Action by Kyle Banker Published by Manning Publications
O'Reilly logo

Chapter 6. Updates, atomic operations, and deletes


In this chapter
  • Updating documents
  • Processing documents atomically
  • Category hierarchies and inventory management


To update is to write to existing documents. But to do this effectively requires a thorough understanding of the kinds of document structures available and of the query expressions made possible by MongoDB. Having studied the e-commerce data model throughout the last two chapters, you should have a good sense for the ways in which schemas are designed and queried. We’ll use all of this knowledge in our study of updates.

Specifically, we’ll look more closely at why we model the category hierarchy in such a denormalized way, and how MongoDB’s updates make that structure reasonable. ...

The best content for your career. Discover unlimited learning on demand for around $1/day.