In Informatica we may have to remove the repository objects like mapping or sessions.In such cases we have to check the dependency before removing because one mapping may be dependent on many others, or one workflow can be dependent on many other workflows.Other wise it may cause problems.
To check the dependencies for a mapping you can directly go to the mapping and Click on “Check Dependencies”. This will give you all the dependencies related to a mapping.Here you can find source,target,mappings everything related to the mapping.This will also help in tracing the history of the mapping like the staging part and the source part of the mappings
Similarly you can check for the session and other repository objects in Workflow Manager and Designer. Also you can check the dependencies while checking the object history or checkouts