Azure SQL Database Best Practices

Introduction

Azure SQL Database is a fully managed Platform as a Service (PaaS) database engine that handles most of the database management functions. To maximize its benefits and ensure your applications perform optimally, securely, and cost-effectively, adhering to best practices is crucial. This documentation provides a comprehensive guide to achieving this.

Performance Optimization

Achieving peak performance for your Azure SQL Database involves several key areas:

1. Query Tuning and Indexing

• Analyze query execution plans to identify bottlenecks. Use tools like SQL Server Management Studio (SSMS) or Azure Data Studio.
• Implement appropriate indexes (clustered, non-clustered, columnstore) based on query patterns. Avoid over-indexing.
• Maintain statistics regularly to ensure the query optimizer has accurate information.
• Consider using Automatic tuning features in Azure SQL Database.

2. Resource Provisioning

• Choose the right service tier (General Purpose, Business Critical, Hyperscale) and compute size (DTUs or vCores) based on your workload requirements.
• Monitor resource utilization (CPU, memory, IO) and scale up or down as needed.
• Leverage Elastic Pools for managing multiple databases with variable resource demands.

3. Connection Management

• Use connection pooling to reduce the overhead of establishing new connections.
• Keep connections open for as long as necessary but close them when not actively in use to free up resources.

Security Considerations

Securing your Azure SQL Database is paramount. Implement a layered security approach:

1. Network Security

• Configure firewall rules to restrict access to your database server.
• Use Private Link to connect to your Azure SQL Database over a private endpoint, avoiding public internet exposure.
• Enable Transparent Data Encryption (TDE) to encrypt data at rest.

2. Authentication and Authorization

• Prefer Azure Active Directory (Azure AD) authentication over SQL authentication for enhanced security and centralized management.
• Implement the principle of least privilege for user roles and permissions.
• Regularly audit access and permissions.

3. Data Protection

• Use Dynamic Data Masking to mask sensitive data for non-privileged users.
• Implement Row-Level Security (RLS) to control access to specific rows in a table.
• Regularly backup your database and test restore procedures.

Management & Monitoring

Effective management and monitoring are key to maintaining a healthy database environment.

• Leverage Azure Monitor and SQL Insights for comprehensive performance and health monitoring.
• Set up alerts for critical performance metrics and potential issues.
• Automate routine tasks such as maintenance, backups, and index rebuilding using Azure Automation or SQL Agent jobs (if applicable).
• Keep your database schema well-documented.

Resilience & High Availability

Ensure your applications remain available even in the face of failures.

• Understand the built-in high availability features of Azure SQL Database (e.g., automatic failover for Business Critical tier).
• Configure Point-in-Time Restore (PITR) for recovery from accidental data loss or corruption.
• Explore geo-replication and Active Geo-Replication for disaster recovery scenarios.
• Design your application to be resilient to transient database connection errors. Implement retry logic.

Cost Management

Optimize costs without sacrificing performance or reliability.

• Right-size your database tier and compute based on actual usage.
• Utilize Reserved Instances for predictable, long-term workloads to get significant discounts.
• Consider serverless compute options for workloads with intermittent or unpredictable usage patterns.
• Monitor spending using Azure Cost Management + Billing tools.