Toad Data Modeler!

MySQL Workbench is a unified visual tool for database architects, developers, and DBAs. MySQL Workbench provides data modeling, SQL development, and comprehensive administration tools for server configuration, user administration, and much more. MySQL Workbench is available on Windows, Linux and Mac OS.

Oracle SQL Developer Data Modeler is a free graphical tool that enhances productivity and simplifies data modeling tasks. Using Oracle SQL Developer Data Modeler users can create, browse and edit, logical, relational, physical, multi-dimensional, and data type models. The Data Modeler provides forward and reverse engineering capabilities and supports collaborative development through integrated source code control. The Data Modeler can be used in both traditional and in Cloud environments.

erwin Data Modeler provides a collaborative environment to manage enterprise data though an intuitive, graphical interface. With a centralized view of key data definitions, you can leverage information as a strategic asset and more efficiently manage your data resources to save time and money.

Open source data modeling tool designed for PostgreSQL. No more DDL commands written by hand. Let pgModeler do the job for you! Easily create and edit database models with simple and intuitive interface.

DBDesigner 4 is a visual database design system that integrates database design, modeling, creation and maintenance into a single, seamless environment.

Free visual data modeling inspection tool for most popular one-way reverse-engineered relational databases. With a generic graphical interface, and auto-generated detailed, structural, relationships, simple, graph or topological models. Expanded, collapsed, minimized or transparent shapes. Chain relationships, custom joins and aliases, to enhance your model without altering the database itself.