DBLE vs Heimdall Database Proxy

DBLE is free, open-source middleware for scaling MySQL through sharding. It uses the MySQL protocol and can replace MySQL in many cases without application code changes. Teams can configure hash, modulo, time-based, range-based, or custom sharding, along with global and ER tables. DBLE lists query routing, connection pooling, load balancing, automatic failover, read/write separation, master-slave expansion, and ZooKeeper cluster deployment. SQL support includes SQL 92 and MySQL dialect features such as joins, unions, grouping, ordering, and distinct queries; some features remain on its roadmap. Query optimization addresses global-table joins, sharded tables, ER relations, and subqueries. Distributed transactions use two-phase commit in normal or XA modes, with XA depending on MySQL 5.7 XA transactions, backend availability, and disk reliability. Security controls include password encryption, IP allowlists, and SQL denylists. Explain plans, MySQL-compatible slow logs, and slow-query reports support operations. DBLE is self-hosted on Linux and GPL-2.0 licensed. The open-source plan costs nothing.

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.