SQL Developer - Oracle SQL Developer is a free, development environment that simplifies the management of Oracle Database in both traditional and Cloud deployments.
4D - 4D is a relational database management system and IDE.
Toad Edge - Windows GUI for MySQL. SQL Syntax Check. Freeware (Basic Features) & Payware (Extended Features).
Informix - IBM Informix is a secure embeddable database optimized for OLTP and IoT data. Informix can seamlessly integrate SQL, NoSQL/JSON, and time series and spatial data.
DbVisualizer - DbVisualizer is the universal database tool for developers, DBAs and analysts.
LiveCode Platform - It is Both Under the GPL and it is also Proprietary if using the GPL version the software you make...