title: Use of _include in FHIR
body: <p>In the FHIR query spec it states that the _include parameter can be added to the query URL to request that specified referenced resources are returned in full to prevent further network requests to retrieve these resources.</p>
  
  <p>i.e.</p>
  
  <p>diagnosticreport/search?_include=DiagnosticReport.subject&amp;_include=Patient.provider</p>
  
  <p>This construct requires that you know the resources that are going to be referenced in the result set in advance of the query being made. I suspect for resources such as "Observation" where there will potentially be many profiles with each profile potentially having different extensions, this will not be the case.</p>
  
  <p>Is it feasible to have a syntax whereby all of the referenced resources are "included"?</p>