Developing Solutions for Microsoft Azure (AZ-204) Practice Exam

How do logical partitions relate to physical partitions in Azure Cosmos DB?

1. Logical partitions are collections of physical partitions.

2. Physical partitions are collections of logical partitions.

3. There's no relationship between physical and logical partitions.

4. Logical partitions are independent of physical partitions.

The correct answer is: Physical partitions are collections of logical partitions.

In Azure Cosmos DB, the relationship between logical partitions and physical partitions is such that physical partitions serve as the underlying infrastructure for storing logical partitions. Each logical partition can contain multiple items, and these items are all stored within a physical partition that enables scalability and performance. Physical partitions are designed to handle a certain amount of storage and throughput, allowing Azure Cosmos DB to efficiently manage large volumes of data. As data grows and the demand for resources increases, more physical partitions may be allocated to accommodate additional logical partitions. This relationship allows Cosmos DB to seamlessly scale out and distribute data while maintaining the logical organization that developers rely on when querying and managing data. Understanding this hierarchy is crucial because it informs how data is managed, queried, and optimized for performance in Azure Cosmos DB. Developers should recognize that while logical partitions provide a way to logically group data, it is the physical partitions that ultimately determine data storage, performance, and resource allocation.