Azure 17: Azure Cosmos DB
easy⏱ 5 mincourseazure
Cosmos DB Core
Account > Database > Container > Items (JSON). The Partition Key determines data distribution. Throughput measured in RU/s (Request Units). APIs: NoSQL (recommended), MongoDB, Cassandra, Gremlin, Table. Consistency levels: Strong, Bounded Staleness, Session (default), Consistent Prefix, Eventual.
const { container } = await database.containers.createIfNotExists({
id: 'users', partitionKey: { paths: ['/country'] }
});
await container.items.create({ id: '1', country: 'US', name: 'Alice' });
Simulate Cosmos DB with RU tracking
Create a CosmosDBClient with createItem, readItem (by id + partition key), and query (with filter). Track estimated RU cost for each operation.
Quiz: Default Consistency
What is the default consistency level? Session — reads never see out-of-order writes within a session. Good balance between latency and correctness.