Schemaless Data
XNAT uses an XML schema to declare datatypes and variables. However it offers several mechanisms to store data that do not fit in the schemas. The trade off is in general that those data cannot be queried using the search engine.
Parameters
Key/value mechanism accessible at the assessor and reconstruction levels.
>>> assessor.set_param('one', '1')
>>> assessor.set_param('two', '2')
>>> assessor.params()
['one', 'two']
>>> assessor.get_param('two')
'2'
Warning
Currently a parameter cannot be deleted.