Imports and exports

Note

Attention: the import procedure is about to change in the next version of DDI on Rails.

New import design (DDI on Rails 2)

The new imports are closely tied to the data model. Many “additional functionality” was removed, e.g., the link between logical variables and question items is now in an independent import; and is no longer part of either the logical variables import or the questions import.

Import formats

CSV formats

Markdown
In most imports, there is a description field using Markdown. For more information about the Markdown markup language, see: Daring Fireball.
Conventions

Some fields in the CSV exports are not part of the import. Those fields start with view_ variables and datasets.

Columns with the internal_ prefix are indended for internal use only and will not be imported (e.g. internal_comment).

Language codes, for all translation purposes: ISO 639-1

XML formats

Endnote
Publications in Endnote’s XML export.
r2ddi
DDI-Codebook-based XML, generated by r2ddi.
QeDML
QeDML-XML from QLIB.

Other formats

Endnote keys
Endnote keys are a special import of two columns (accession number and keywords) in addition to the normal XML import. Endnote exports everything but the keywords to XML what makes this import neccessary.

Conventions

  • Name identifiers: all names are set to lower case during import. This means that names must be unique despite their capitalization. Furthermore, only a limited set of characters is allowed in names: letters (a-z), numbers (0-9), dash (-), and underscore (_).

Import structure

Top level

import/
|-- system/       # -> system-wide imports
|-- study-first/  # \
|-- study-second/ #  }-> one folder per study
|-- study-third/  # /

All levels

ddionrails/
|-- study.md
|-- variables.csv
|-- ...all other csv files...
|-- datasets/
|   |-- version/
|   |   |-- ...dataset descriptions in DDI-C-XML...
|-- files/
|   |-- ...all files for public folder...
|-- instruments/
|-- qedml/
|   |-- ...questionnaires in QeDML-XML-format...
|-- topics/

Formats