Some repository objects contain other repository objects. For example, workflows contain sessions and tasks, sessions contain mappings, and mappings contain at least one source and target definition.

You obtain an in-use lock on an object when you view it. You can view an object used by another object without affecting the other object. However, if you save changes to an object used by other objects, the repository might mark the other objects invalid. Before using invalidated objects, you must validate them.

For example, you open a mapping used by a session, delete a transformation, and save the changes. When you save the mapping, the repository notes the mapping has been changed, and marks the session and every other session using the mapping invalid. The change might invalidate any workflow containing the session.