A well-optimised SQL database ensures high performance, data integrity, and security. This guide covers general SQL health check principles and Microsoft SQL Server-specific best practices.
General SQL Health Check
1. Performance Tuning Basics
- Monitor query execution times using
EXPLAIN (MySQL/PostgreSQL) or Query Execution Plan (MS SQL).
- Avoid using
SELECT *; only query necessary columns.
2. Indexing Best Practices
- Use indexes on frequently searched columns but avoid excessive indexing.
- Monitor index fragmentation and rebuild/reorganise when necessary.
3. Query Optimisation
- Use stored procedures to optimise execution time.
- Optimise JOINs and ensure proper indexing on foreign keys.
4. Security Considerations
- Enforce strong user authentication and role-based access control (RBAC).
- Prevent SQL injection by using prepared statements.
MS SQL Server-Specific Health Check
1. SQL Server Profiler
- Identify slow queries and resource-heavy operations.
- Monitor deadlocks and blocking processes.
2. Query Store
- Enable Query Store to track query performance over time.
- Identify query plan regressions and optimise accordingly.
3. TempDB Configuration
- Ensure TempDB has multiple data files for scalability.
- Monitor TempDB growth and prevent uncontrolled expansion.
4. Memory & CPU Optimisation
- Set appropriate memory limits to prevent SQL Server from consuming all available RAM.
- Monitor CPU usage and optimise queries to reduce load.
Conclusion & Best Practices
Regular health checks improve SQL database performance and security. Whether using MySQL, PostgreSQL, or MS SQL Server, applying best practices such as query optimisation, indexing, and security measures ensures a well-maintained database.