DBeaver - DBeaver - Universal Database Manager and SQL Client.
FlameRobin - FlameRobin is a cross-platform, open-source database administration tool for Firebird DBMS.
Database Browser - Database browser is an universal table editor.
RazorSQL - RazorSQL is an SQL Editor and SQL database query tool for macOS, Windows, Linux, and Mac OS X.
SQuirreL SQL - SQuirreL SQL is an open-source Java SQL Client program for any JDBC compliant database
IBExpert - IBExpert website