TerraER is a free, open-source application that makes the understanding of data modeling much easier. The tool is addressed to academics, specially to support modeling database courses.

The software is basically an editor and has the following basic features:

• Modeling of Entity Relationship Models (ER)
• Intuitive interface
• Easy to learn
• Save in XML
• Clipboard Transfer
• Printing

More important, TerraER is useful and facilitate the understanding of data modeling, since we easily create, update, retrieve, and save ER models.

Since you finish your ER model, you are quite close to realize your model in your preferred DBMS, such as MySql, Oracle, SQL Server, DB2, etc.

Note: While the software is classified as free, it is actually donationware. Please consider making a donation to help support development.