We have received quite a lot of interest in using SQL on FHIR data. As you know, FHIR data is encoded in the form of a complex directed graph, and thus you can not easily query it with traditional SQL queries or business intelligence tools. Some customers have noticed that the "FHIR search tables" in IRIS for Health have flattened part of the FHIR graph, and have tried to use them for analytics. This is an undocumented and unsupported part of IRIS for Health, and can change without notice.
The good news is we are working on a product supported feature for IRIS for Health to extract data from the FHIR repository and place it in a SQL schema under user control. There is no release date at this time, but when we are closer to release, we will publish an announcement.
Patrick W. Jamieson, M.D.
Product Manager, IRIS for Health