View source for Referencing (Normalization)

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'''Category:''' Data Modeling & Partitioning

'''Summary:''' Storing related entities as separate documents linked by an id reference.

== Overview ==
Referencing is a data modeling technique where related entities are stored as separate documents (potentially in separate containers), with one document holding a reference (an id or foreign key-like property) to the other. It's preferred when related data changes independently, is large, is shared across many parent entities, or has a 1:many or many:many relationship that would make embedding impractical.

== More Info & Links ==
* [https://learn.microsoft.com/en-us/azure/cosmos-db/nosql/modeling-data Microsoft Learn: Data modeling in Azure Cosmos DB]

== DP-420 Style Practice Questions ==
'''Q1.''' When is referencing (normalizing) preferred over embedding in Azure Cosmos DB data modeling?
* A. When related data changes independently, is large, or is shared across many parents
* B. When the related entities are always retrieved together
* C. When minimizing the number of read round-trips is the top priority
* D. When the relationship is strictly 1:1 and small

'''Q2.''' What is a trade-off of using referencing instead of embedding?
* A. It may require multiple round trips (and more RUs) to retrieve related data
* B. It always reduces the total storage used
* C. It removes the need for a partition key
* D. It guarantees strong consistency automatically

== Answer Key ==
''Answers are listed at the very end so you can attempt the questions first.''

* '''Q1 (Referencing (Normalization)):''' A. When related data changes independently, is large, or is shared across many parents — Referencing suits data with independent lifecycles, large size, or many-to-many/shared relationships.
* '''Q2 (Referencing (Normalization)):''' A. It may require multiple round trips (and more RUs) to retrieve related data — Referencing requires additional queries/round trips to join related documents, unlike embedding.

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''DP-420: Designing and Implementing Cloud-Native Applications Using Microsoft Azure Cosmos DB — term detail page''

[[Category:DP-420 Terminology]]
[[Category:Data Modeling & Partitioning]]