If you are using a MS SQL datastore, a bug prevents attributes from it being used when accessing resources. Categories based on the datastore are not applied and datastore attributes drawn from it are not released.
The workaround is to pass the username field twice. E.g:
This workaround allows the runtime to use the attributes but in the administration console neither the test query button, nor the update from datastore button on the attribute names tab will work with the second parameter present. You must run those before you add the workaround.