This custom operation (lightweight alternative to transaction) simplifies upsert (update or create) resources into FHIR server. Just put array of resources (with id's) on /
PUT /​- status: draftclass: {code: IMP}period: {start: "2013-06-08T10:57:34", end: "2013-06-08T12:00:00"}resourceType: Encounterid: enc-1​- status: draftclass: {code: IMP}period: {start: "2013-06-08T11:00:05", end: "2013-06-08T11:30:00"}resourceType: Encounterid: enc-2​- status: draftclass: {code: AMB}period: {start: "2013-06-08T10:21:01", end: "2013-06-08T11:42:11"}resourceType: Encounterid: enc-3​- status: draftclass: {code: IMP}period: {start: "2013-06-07T09:02:01", end: "2013-06-07T15:10:09"}resourceType: Encounterid: enc-3