SQL Developer - Oracle SQL Developer is a free, development environment that simplifies the management of Oracle Database in both traditional and Cloud deployments.
DBeaver - DBeaver - Universal Database Manager and SQL Client.
DataGrip - Tool for SQL and databases
HeidiSQL - HeidiSQL is a powerful and easy client for MySQL, MariaDB, Microsoft SQL Server and PostgreSQL. Open source and entirely free to use.
dbForge Studio for Oracle - dbForge Studio for Oracle is a powerful IDE used by Oracle SQL developers to development, administration, management, and synchronization of Oracle databases via a handy GUI.
Navicat - Powerful database management & design tool for Win, Mac & Linux. With intuitive GUI, user manages MySQL, MariaDB, SQL Server, SQLite, Oracle & PostgreSQL DB easily.