The RIS format is sort of an interchange format for bibliographic data that most commercial bibliography software can read and create. RefDB accepts this format as a native input format. It is a tagged format, i.e. each logical line starts with a tag which describes the contents of that line. refdb-mode ships with an additional mode called ris-mode (ris.el) which adds syntax highlighting as well as some basic editing support for this data format to Emacs. The RIS format is fairly compact and easy to understand. This format is a good choice as the default output format, as it is both convenient to read and easy to update the database with changes.

This is an XML application which describes the RIS standard (with minor extensions) using a syntax familiar to anyone who writes XML or SGML documents. It is more verbose than the RIS format, but it can also be used to update the database directly if you want to commit changes. risx has an edge over RIS in terms of validation. If you have nxml-mode associated with XML files, refdb-mode will use this mode to display query results in RISX format as well as source files containing bibliographic data. nxml-mode contains a validating parser, so you have an immediate feedback whether or not your changes to the data are valid. refdb-mode will refuse to add or update XML data if nxml-mode indicates they are not valid. This format is a good choice if you are familiar with XML data anyway and if you are not put off by its verbosity.

This is another XML application which describes extended notes. This is the only input format available for extended notes. These notes are not part of your bibliographic data, but they can be attached to a variety of objects in your reference database, like (obviously) bibliographic records, but also author names, periodicals, and keywords. Use this format to add and update extended notes. When using nxml-mode for XML data, you'll also get validation for free.

This is yet another XML application which describes bibliography and citation styles. This is the only available import and export format for style data. When using nxml-mode for XML data, you'll also enjoy the benefits of real-time validation.

All other formats can only be used to export or view reference and notes data. They are of limited use in the interactive use of refdb-mode, but come in handy if you need to export data for other purposes.

refdb-mode uses a few menu commands to select and customize the output format of reference and note queries (remember that there is no choice for extended notes and citation styles).

The RefDB → Customize Data Output → Select Reference Output Type menu command pops up a list of available output formats. After selecting one of the available formats, all future calls to a command which returns reference data will use this output format.

The RefDB → Customize Data Output → Select Notes Output Type menu command works exactly the same and selects the output format of extended notes.

The RefDB → Customize Data Output → Select Output Format menu command selects how much information is displayed in the reference data. RIS and risx always return all available data, as these formats are meant to add and update datasets in the database. The remaining formats show only the core bibliographic data. By default, they do not show information like the reprint status or the abstract. If you select All fields here, these formats will also display all information. If you select More (additional) fields, a customizable subset of the additional fields will be displayed. Use the RefDB → Customize Data Output → Select Additional Data Fields menu command to select the additional fields that you would like to be displayed. The IDs only can be used in conjunction with RIS output. Some commands of the command-line clients use this kind of minimized RIS data as input (this is currently not supported by refdb-mode).