usql - Universal command-line interface for SQL databases
Errbit - The open source error catcher that's Airbrake API compliant
Redsmin - All-in-One GUI for Redis. Thightly crafted developer oriented, online real-time monitoring and administration service for Redis.
HeidiSQL - HeidiSQL is a powerful and easy client for MySQL, MariaDB, Microsoft SQL Server and PostgreSQL. Open source and entirely free to use.
mycli - A CLI for MySQL with auto-completion and syntax highlighting
DBeaver - DBeaver - Universal Database Manager and SQL Client.