Database modeling tool [closed]

Answer 1

I would suggest SQL Power Architect for the following reasons (from the official feature list):

• Accesses source databases via JDBC
• Connects to multiple source databases concurrently
• Compares data models & database structures and identifies discrepancies
• Drag-and-drop source tables & columns into the playpen
• Remembers the origin of each column
• Generates source-to-target visual Mapping Reports
• Forward/reverse engineers PostgreSQL, Oracle, MS SQL Server & more
• Saves source data structure snapshots in the project, so you can work remotely
• All project data is stored in an easy-to-parse XML format
• OLAP schema modeling: Cubes, Measures, Dimensions, Hierarchies & Levels
• GPL (version 3) licensed

...and a couple reasons of my own:

• runs on basically any platform
• has fairly nice keyboard support for fast model development
• relatively useful diagram auto-layout

Answer 2

Why would you not want to use the built-in Data Diagrammer?

If you just want to draw your tables, have a look at Dia. In the Links section you find some tools that convert the drawing into SQL.