FHIR Chat · Searching with _elements and choice types · implementers

Stream: implementers

Topic: Searching with _elements and choice types

Josh Mandel (Dec 05 2019 at 20:43):

If I want to search for Observation?_elements= in a query to return Observations with just the valueQuantity (and not, say, category or other "extraneous" data), the spec says:

The _elements parameter consists of a comma-separated list of base element names

I'm not sure what the base element name is for Observation.valueQuantity. Official profile suggests value[x] ... but I see variable behavior across references servers.

Grahame Grieve (Dec 05 2019 at 20:45):

I don't think we ever discussed this

Josh Mandel (Dec 05 2019 at 20:45):

With HAPI, the following all work:

But this does't:

http://hapi.fhir.org/baseR4/Observation?_format=json&_pretty=true&_elements=value[x]

Josh Mandel (Dec 05 2019 at 20:46):

With Grahame's server, the following do not work:

(And I can't figure out what does work.)

Grahame Grieve (Dec 05 2019 at 20:47):

nothing will for value - bug in my code generator

Josh Mandel (Dec 05 2019 at 20:47):

OK, I'll add a Jira issue. @Grahame Grieve for the record, is there a way to coax your server into returning Observation via _elements ?

Josh Mandel (Dec 05 2019 at 20:47):

Ah, OK.

Grahame Grieve (Dec 05 2019 at 20:48):

all the other elements should be bound by _summary, but choice elements are not

Josh Mandel (Dec 05 2019 at 20:50):

Josh Mandel (Dec 05 2019 at 20:50):

(This is coming up because I've been noodling on how to express proactive policies about what queries to allow/deny for a given client. )

Michele Mottini (Dec 05 2019 at 20:54):

_elements=value on our server

Paul Church (Dec 05 2019 at 21:00):

Also _elements=value on GCP. There's no way to ask for valueQuantity specifically and omit other types though, do people want that?

nicola (RIO/SS) (Dec 10 2019 at 05:09):

Same on Aidbox. Just reminder - Observation.value.x would eliminate this problem. One logical inconsistency brings many anomalies.

Last updated: Apr 12 2022 at 19:14 UTC