Azure Sql

Azure SQL Database is the fully managed SQL Server in the cloud — enterprise-grade relational database with full T-SQL compatibility, built-in HA (99.99% SLA), automated backups, and point-in-time restore. For agents: Managed Identity enables passwordless database connections from Azure services (no connection string secrets). pyodbc with Azure Active Directory auth is the standard Python access pattern. ARM API manages database lifecycle (create, scale, pause/resume serverless). Serverless tier auto-pauses during inactivity — zero cost when idle. Confidence is docs-derived.

Query access via pyodbc (Python). conn = pyodbc.connect("DRIVER={ODBC Driver 18 for SQL Server};SERVER={server}.database.windows.net;DATABASE={db};Authentication=ActiveDirectoryMsi") — Managed Identity auth (no password). cursor = conn.cursor(). cursor.execute("SELECT TOP 10 * FROM users WHERE plan = ?", ("pro",)). cursor.fetchall() retrieves results. cursor.execute("INSERT INTO events (user_id, event, created_at) VALUES (?, ?, GETDATE())", (user_id, event)). conn.commit(). ARM Management API: PUT /subscriptions/{sub}/resourceGroups/{rg}/providers/Microsoft.Sql/servers/{server}/databases/{db} creates/updates database ({properties: {requestedServiceObjectiveName: "S0", edition: "Standard"}}). Elastic pools: manage via ARM at /elasticPools.

Managed Identity (recommended): no stored credentials — configure server firewall to allow Azure services + grant db_datareader/db_datawriter to Managed Identity. Connection string: alternative with username/password (less preferred). HTTPS enforced for management API. Azure AD auth: connect string uses Authentication=ActiveDirectoryMsi or ActiveDirectoryServicePrincipal. Firewall rules: must allow client IP (or Azure services) before connecting. SQL Server auth: legacy option (username + password) for compatibility.

pyodbc exceptions (pyodbc.Error, pyodbc.OperationalError for connection issues). Connection retry: transient connection failures common — implement retry logic (Azure best practice). T-SQL errors: cursor.execute raises pyodbc.ProgrammingError for invalid SQL. Serverless auto-pause: ~60s to resume from paused state — budget for cold start. Elastic pool: multiple DBs share DTUs — monitor DTU contention. Azure SQL uptime at status.azure.com. DTU vs. vCore: two pricing models — vCore recommended for predictable workloads; serverless for variable. Geo-replication: async read replicas in other regions — failover via ARM API.

learn.microsoft.com/azure/azure-sql/database covers quickstart guides, Managed Identity setup, T-SQL reference, performance tuning, and high availability documentation. Getting started: Azure free tier (32GB serverless free), create server + database, connect via pyodbc — first query in under 10 minutes. pyodbc: pip install pyodbc (requires ODBC driver 18). Terraform: azurerm_mssql_database. Community via Microsoft Q&A (azure-sql-database tag) and Stack Overflow. Comprehensive documentation for an enterprise relational database.