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However, this is not always convenient. If the original instance has many custom fields, this could make the load into another instance unnecessarily complex and increase the risk of unexpected effects on other projects. So, the app offers options for those Jira admins who wish to export only those custom fields used by the project configuration, excluding the rest of the custom fields from the export file.
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Since version 2.2.3 of Project Configurator, there is an intermediate filtering option: "Only those used in projects (no values considered)".” This option will export only custom fields used by the exported projects, but it ignores whether there are values set for those fields in issues of the exported projects.
In terms of the criteria above, this is equivalent to ignoring the last condition , after the last "OR". This means a custom field which that is not used in any of the project schemes or workflows and is not visible in any of the screens used by the project will not be exported, even if some issues in the exported projects have values for those custom fields.
This intermediate option is intended only for users with large databases, and when the query evaluating the condition about custom field values might have an excessive impact on times required for exporting. In all other cases, its use is not recommended.
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Custom Fields Used in Dashboard Gadgets
If you are exporting dashboards, and a gadget is exported that uses a given custom field (for example, it is one of the fields included in the columns for the Assigned to Me Gadget), this custom field will be included in the export, regardless if it is used by an exported project or not.