Data model

A freshly installed instance of RDMO is not very useful without a questionnaire to fill out by the user and a set of DMP templates later to be populated by the given answers. The main idea of RDMO is that every question and every output can be customized by you. This, however, introduces a certain level of complexity. RDMO employs a datamodel organized along different Django apps and models (representing database tables). A graphical overview is given in the figure below:

Overview of the RDMO data model

For most users, the structured interview will be the most visible part of RDMO. It is configured using catalogs, sections, pages (since RDMO 2.0), questionsets, and questions. A single installation of RDMO can have multiple catalogs. The user can choose, from the available catalogs, which catalog is used for his or her project.

A catalog contains a number of sections, which themselves have pages. A page represents one visible page in the interview and contains questions and question sets. A question has a text, which will be shown in bold to the user and an additional (optional) help text. It also has a widget type, which determines which interface widget is presented to the user (e.g. text field, select field, radio buttons, checkboxes, etc.). Question sets can contain questions or again question sets themselves and allow for a nested interview structure.

Since RDMO 2.0 catalogs, sections, pages, question sets and questions use so called many-to-many relations between each other. This means that e.g. one catalog can have many sections, but one section can be also part of many catalogs. This aims to improve the reusability of the different elements. When creating a new catalog/section/page with one or more sub-elements which are also available in other elements, those elements do not need to be copied and separately maintained anymore.

The domain model is the central part of the data model and connects the questions from the questionnaire with the answers given by the user. It is organized as a tree-like structure. Every piece of information about a user’s project is represented by an attribute. In this sense, these attributes can be compared to a variable in source code. Attributes are the leaves of the domain model tree, that organize the connections between the different entities assigned to them. Much like files are organized along directories on a disk. Every question or questionset set must have an attribute to be connected to. An example would be the attribute with the path project/schedule/project_start for the start date of the project. The attribute itself has the key project_start and resides in the attribute schedule, which itself is located in the project.

Prior to version 0.11.0 (released in December 2018), the domain model distinguished between Entities as inner nodes and Attributes as leafs of the tree structure. Due to the data model refactoring in 0.11.0, this is no longer the case and all entries in the domain are Attributes. Note that in older publications on RDMO’s domain model you might still find this nomenclature.

Conditions can be connected to questionsets. Conditions control if the questionsets will or will not be shown to the user during the interview. Depending on the answer to certain questions, the condition will be evaluated and the related questionset will be shown or hidden. Conditions are also needed to disable/enable option sets and tasks and can also be used in views. Conditions are configured with a source attribute, which will be evaluated, a relation like “equal” or “greater than”, and a target. The target is a text string or an option. As an example, if the source is the attribute project/legal_aspects/ipr/yesno, the relation is “equal to”, and the target text is “1”. The condition will be true for a project where the answer to the question connected to the attribute project/legal_aspects/ipr/yesno is “1” (or “yes” for a yesno widget). Conditions configured under /conditions are available in the management menu.

Views allow for custom DMP templates in RDMO. To this purpose, every view has a template which can be edited using the Django template syntax, which is based on HTML. Views have also a title and a help text to be shown in the project overview. Views are configured under /views available in the management menu. More documentation about editing views can be found here.

After filling out the interview, the user will be presented with follow up tasks based on his/her answers. A task has a title and a text. Time frames can be added to tasks, which themselves are evaluating attributes of the value type “datetime”, to use answers such as the beginning or the end of a project to compute meaningful tasks. Most of the time tasks will have a condition connected to them, to determine if this task is needed for a particular project or not. Tasks configured under /tasks are available in the management menu.

All elements contain a set of common parameters: the URI prefix, the URI path, and an internal comment.

The URI prefix is the first part of the URI. As every element has a URI, every element does obviously also have a URI prefix. Semantically the prefix is only relevant when different RDMO instances share data between each other. In this case the URI prefix is used to determine which instance the data belong to. You may think of it as a kind of unique instance identifier.

When you import a question catalog or any other content from another institution these imports do have a URI prefix different from yours. If you change elements from these third party imports we strongly recommend to always adjust the URI prefix into your own one to make the changes persistent. This is necessary because a re-import of the third party content will overwrite by using the URI as identifier. Data in your database having the same URI as the imported ones will get updated and so overwritten. Please do also look into Export and Import page for a little more detail.

By convention the URI prefix has to look like a URL. It does not have to be a valid URL in terms of being resolvable. In principle you could use any kind of string as long as it fits the scheme but we recommend to use the URL of your RDMO instance. The URI prefix has to start with http:// or https://. Afterwards there has to be a host name. Anything further like for instance a path is optional. Valid URI prefixes for example are: or

In edit forms of elements you will find a button looking like this . It can be used to automatically put the default URI prefix into the open form. This is very useful especially if you do not exactly remember or know the default value of your RDMO installation. The default URI prefix that this button applies, is defined with the value for DEFAULT_URI_PREFIX in settings of your instance. The button is only helpful when the value is set, otherwise the default will be ''. We strongly recommend to set your own default URI prefix in the settings, see below for an example that can be added to the


The URI path is used as an internal identifier and determines, together with the URI prefix, the URI of the element.

An internal comment can be used share information to be seen by users with access to the management backend.