Features Comparison of SQL Database and SQL Managed Instance

Azure SQL Database and SQL Managed Instance share a common code base with the latest stable version of SQL Server. Most of the standard SQL language, query processing, and database management features are identical. The features that are common between SQL Server and SQL Database or SQL Managed Instance are:

• Language features - Control of flow language keywords, Cursors, Data types, DML statements, Predicates, Sequence numbers, Stored procedures, and Variables.
• Database features - Automatic tuning (plan forcing), Change tracking, Database collation, Contained databases, Contained users, Data compression, Database configuration settings, Online index operations, Partitioning, and Temporal tables (see getting started guide).
• Security features - Application roles, Dynamic data masking (see getting started guide), Row Level Security, and Threat detection - see getting started guides for SQL Database and SQL Managed Instance.
• Multi-model capabilities - Graph processing, JSON data (see getting started guide), OPENXML, Spatial, OPENJSON, and XML indexes.

Azure manages your databases and guarantees their high-availability. Some features that might affect high-availability or can't be used in PaaS world have limited functionalities in SQL Database and SQL Managed Instance. These features are described in the tables below.

If you need more details about the differences, you can find them in the separate pages:

• Azure SQL Database vs. SQL Server differences
• Azure SQL Managed Instance vs. SQL Server differences

Source: Compare the database engine features of SQL Database and SQL Managed Instance - Azure SQL Database & SQL Managed Instance | Microsoft Learn