Heimdall Database Proxy vs ProxySQL

Heimdall Database Proxy is a data access layer between an application and its database, routing, caching, and securing SQL queries. It can send reads to replicas and writes to primary databases, with replication-lag detection to support consistency. Frequently used queries can be cached with automatic expiry and invalidation rules to reduce database load and latency. Connection pooling can reduce front-side to back-side connections by up to a 1000:1 ratio. The proxy provides live SQL visibility, bottleneck identification, and auto-tuning recommendations, and can run as a transparent sidecar on-premise or in the cloud. Supported databases include MySQL, PostgreSQL, Amazon RDS, Oracle, SQL Server, MariaDB, DB2, Greenplum, and Redshift. Listed cloud integrations include AWS, Azure, Oracle, Google Cloud, and Redis. Active Directory integration supports authentication and authorization. Enterprise Plus includes data masking, GDPR auditing, and honey-tokens. A free Greenplum Community Edition is available for Greenplum use, with pooling, LDAP synchronization for one server, and SQL performance analytics. The AWS Marketplace listing offers a free 30-day trial; technical support for the Community Edition requires an Enterprise upgrade.

ProxySQL is a self-hosted Linux database proxy for MySQL, PostgreSQL and related systems. It scales infrastructure without changes to the application stack or database engine, multiplexing more than 100,000 client connections through a few hundred backend connections. Protocol-aware, regex-based routing can send queries to primary servers, replicas or shards, and can route by user, schema or table. The proxy can cache results without application changes, monitor backend health and reroute traffic during failures. Query mirroring duplicates live traffic for analysis and performance testing, while percentage-based balancing supports gradual shifts. A database firewall is intended to protect against SQL injection and runaway queries. Deployment options include Linux packages, Docker and Kubernetes. ProxySQL is GPLv3-licensed open source, released in 2013. The Community plan is free and includes core features, supported platforms and community channels.