Diagramo - Diagramo is an online flowchart software - diagrams (create, edit and share)
DBeaver - DBeaver - Universal Database Manager and SQL Client.
UML Designer - UML Designer provides a set of common diagrams to work with UML 2.5 models.
DataGrip - Tool for SQL and databases
ARIS Express - ARIS Express is based on the proven ARIS methodology and industry standards.
HeidiSQL - HeidiSQL is a powerful and easy client for MySQL, MariaDB, Microsoft SQL Server and PostgreSQL. Open source and entirely free to use.