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How to make field properties whose values are not persistent

The method for adding field properties has a parameter 'persistent' whose default is true. If you explicitly pass false for this parameter the property will not be persistent. Also see how to add a property.

If a peanut is persistent, only persistent field properties will be saved to-, retrieved from, and searchable in the database.  Sorting by the database is only supported for persistent field properties.

If a peanut is not persistent, the persistency of its field properties has no meaning / is ignored by the framework.