Azure Cosmos DB is a globally distributed, multi-model database service designed for low-latency, elastic scale, and high availability. The concepts that drive performance and cost are the resource model (accounts → databases → containers → items), partitioning, and throughput (RU/s). This cheat sheet focuses on the API for NoSQL (SQL query language) and the operational features you’ll use most: indexing, consistency, change feed, backup/restore, and security.

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