Comparing versions of a model to find differences

You can compare two or three models to find the differences between them. When you compare models in a parallel development environment, the models must have a common ancestor.
You can compare models outside a source-controlled environment or within a team environment using a configuration management system, such as IBM® Rational® ClearCase®. When you compare two versions of a model, their differences are displayed. When you compare three models, two sets of differences are displayed:
  • Differences between one version (the left contributor) and the common ancestor
  • Differences between the other version (the right contributor) and the common ancestor

The differences that conflict between the two sets are displayed as conflicts.

Attention: To prevent data corruption when you compare or merge models, you must have the appropriate patch for both your IBM Rational ClearCase client and server environments. To obtain IBM Rational ClearCase releases and patches, go to