Most applications need somewhere to put their data, and Azure gives you managed database services so you're not the one patching a database server at 2am. This module covers the two broad shapes that data takes and the Azure services built for each: relational, table-and-rows data, and non-relational, document-style data.
It starts with relational data in Azure — provisioning, connecting to, and working with Azure SQL Database, plus where Azure Database for PostgreSQL and MySQL fit alongside it. From there it covers Azure Cosmos DB, Azure's globally distributed, multi-model database service for non-relational data, including the APIs it supports and how request units drive its pricing.
Work through the lessons in order, then continue on to Containers & Kubernetes on Azure.
freeCodeCamp's full AZ-104 course: identity and governance, storage, virtual machines, applications, networking, monitoring, and backup — a comprehensive tour that ties this module's concepts together and doubles as certification prep.