We are going to start importing our old excel sheets containing issues into JIRA, and therefore I've tried out the csv importer. In our use case, I want to import issues only. Users, issue types etc are already set up in JIRA.

To my surprise, new issue types, users and other items are created automatically without any warning upon import. As we already have a fully configured JIRA environment with everything setup, I don't want the importer to create anything new. If it needs to, it is because I've made a mistake in the csv file or the mapping.

The importer should be able to issue a warning before adding new users, issue types or anything else belonging to the JIRA configuration.