Database Proxy
What is a Database Proxy?
A database proxy is an intermediary service that sits between applications and databases, intercepting and managing database connections and queries. It acts as a transparent gateway that can modify, route, cache, or monitor database traffic without requiring changes to the application code.
Problem it Solves
Direct database connections can create bottlenecks, security vulnerabilities, and operational challenges in distributed systems. Database proxies solve these issues by providing connection pooling, load balancing, query optimization, security enforcement, and operational visibility without requiring application modifications.
Key Features
Connection Pooling
Manages a pool of database connections to reduce connection overhead and improve performance.
Load Balancing
Distributes queries across multiple database instances or read replicas.
Query Routing
Routes read queries to replicas and write queries to primary databases.
Caching
Caches frequently accessed query results to reduce database load.
Security
Provides authentication, authorization, and query filtering capabilities.
Common Use Cases
- • Database Sharding: Routing queries to appropriate shards
- • Read/Write Splitting: Directing reads to replicas and writes to primary
- • Connection Management: Pooling connections for high-traffic applications
- • Security Enforcement: Adding authentication and query validation layers
- • Performance Monitoring: Tracking query performance and database metrics
- • Migration Support: Gradual migration between database systems
Popular Database Proxies
- • ProxySQL: High-performance MySQL proxy with advanced routing
- • PgBouncer: Lightweight PostgreSQL connection pooler
- • Vitess: Database clustering system with built-in proxy capabilities
- • MaxScale: MariaDB's database proxy and load balancer
- • AWS RDS Proxy: Managed database proxy service for RDS
Benefits
- • Improved Performance: Connection pooling and query caching
- • High Availability: Automatic failover and load distribution
- • Scalability: Easy addition of read replicas and shards
- • Security: Centralized access control and query filtering
- • Transparency: No application code changes required
- • Operational Visibility: Centralized monitoring and logging
Considerations
- • Additional Latency: Extra network hop and processing time
- • Single Point of Failure: Proxy itself can become a bottleneck
- • Complexity: Additional component to deploy and maintain
- • Protocol Compatibility: Must support specific database protocols