The valid_extensions relation is used to find the file extensions allowed to be archived for data identified by the data_id of the mission pipeline. C3 The mission pipeline OSF data_id used to archive datasets. C3 This is the file extension name that is either required, allowed, or forbidden to be archived. A wildcard character, the asterisk, may be used with the valid_type field set to R, to indicate all extensions are accepted. C1 The value R indicates a required extension, a value O indicates an optional extension, and a value F indicates a forbidden extension. VALID_EXTENSIONS_TYPE This table specifies the valid extensions for an OSF data_id. OPUS unique clustered