What will happen to past issues/fields if I change the scheme/field configuration of the Project?

[radu_johansen]

As the title says, I'm interested in changing the scheme (issue types) and field configuration of a project but I don't know how this will affect past issues and their fields. 

The change I want to make is to a new scheme / configuration which is NOT shared by other projects -  the goal being to eliminate from my project issue types and fields which I don't use in it. 

Will issue types/fields used in the old scheme just disappear or be changed, or will they simply not be available to reintroduce in the project for future issues?  

[Jasmeet Kaur · Accepted solution]

Hello @radu_johansen 

Welcome to the Atlassian Community!

Here's what happens when you change the issue type scheme and field configuration of a Jira project, especially when moving to a new, non-shared scheme to eliminate unused issue types and fields

Issue Types

• If you remove issue types from the scheme:
  Any existing issues in your project that use an issue type you are removing will need to be re-mapped to one of the remaining issue types in the new scheme. Jira will prompt you to select which new issue type each set of "orphaned" issues should be converted to. You cannot leave issues without a valid issue type.

• For future issues:
  Only the issue types in your new scheme will be available for creation. The removed issue types will not be available for new issues in this project, but they are not deleted from Jira and can still be used in other projects if those projects' schemes include them. 

Fields and Field Configuration

• If you remove fields from the field configuration or screens:
  The data in those fields for existing issues is not deleted—it is simply hidden from the UI. If you later re-add the field to the configuration, the data will reappear in those issues.

• For future issues:
  Only the fields present in your new configuration will be available to users. Removed fields cannot be filled in for new issues, but again, the field and its data are not deleted from the database unless you delete the field entirely from Jira

Best Practices

• Back up your data before making major scheme/configuration changes.

• Test changes in a staging environment if possible, to see the impact on existing issues.

• Review field mappings when changing issue types to ensure important data is not lost or hidden.

Thank you!