Once a custom field has been created, you can edit its details at any time. You may already notice that there is a Configure option and an Edit option for each custom field. It may be confusing in the beginning to differentiate between the two. Configure specifies options related to the custom field context, which we will discuss in the following sections. Edit specifies options that are global across Jira for the custom field; these include its name, description, and search templates:

1. Browse to the Custom fields page
2. Select the Edit option by clicking on the cog icon for the custom field you wish to edit from the list of custom fields
3. Change the custom field's details, such as its name or search template
4. Click on the Update button to apply the changes

When making changes to the search templates for your custom fields, it is important to note that, while the change will take effect immediately, you need to perform a full system re-index in order for Jira to return the correct search results. This is because, for each search template, the underlying search data structure may be different, and Jira will need to update its search index for the newly applied search template.

For example, if you have a custom field that did not have a searcher and you have just applied a searcher to it, no results will be returned until you re-index Jira. When you make changes to the search template, Jira will alert you with a message that a re-index will be required, as shown in the following screenshot:

We will discuss searching and indexing in more detail in Chapter 10, Searching, Reporting, and Analysis.

You can also delete existing custom fields, as follows:

1. Browse to the Custom fields page
2. Select the Delete option by clicking on the tools icon for the custom field you wish to delete
3. Click on the Delete button to delete the custom field

Once deleted, you cannot get the custom field back, and you will not be able to retrieve and search the data held by those fields. If you try to create another custom field of the same type and name, it will not inherit the data from the previous custom field, as Jira assigns unique identifiers to each of them. It is highly recommended to back up your Jira project before you delete the field unless you are absolutely sure you do not need it.