Discover how a bimodal integration strategy can address the major data management challenges facing your organization today.
Get the Report →Access FHIR Data as a Remote Oracle Database
Use the Oracle ODBC Gateway and Heterogeneous Services technology to access FHIR data from your Oracle system.
The Oracle Database Gateway for ODBC and Heterogeneous Services technology enable you to connect to ODBC data sources as remote Oracle databases. This article shows how to use the CData ODBC Driver for FHIR to create a database link from FHIR to Oracle and to query FHIR data through the SQL*Plus tool. You can also create the database link and execute queries from SQL Developer.
Connect to FHIR as an ODBC Data Source
Information for connecting to FHIR follows, along with different instructions for configuring a DSN in Windows and Linux environments.
Set URL to the Service Base URL of the FHIR server. This is the address where the resources are defined in the FHIR server you would like to connect to. Set ConnectionType to a supported connection type. Set ContentType to the format of your documents. Set AuthScheme based on the authentication requirements for your FHIR server.
Generic, Azure-based, AWS-based, and Google-based FHIR server implementations are supported.
Sample Service Base URLs
- Generic: http://my_fhir_server/r4b/
- Azure: https://MY_AZURE_FHIR.azurehealthcareapis.com/
- AWS: https://healthlake.REGION.amazonaws.com/datastore/DATASTORE_ID/r4/
- Google: https://healthcare.googleapis.com/v1/projects/PROJECT_ID/locations/LOCATION/datasets/DATASET_ID/fhirStores/FHIR_STORE_ID/fhir/
Generic FHIR Instances
The product supports connections to custom instances of FHIR. Authentication to custom FHIR servers is handled via OAuth (read more about OAuth in the Help documentation. Before you can connect to custom FHIR instances, you must set ConnectionType to Generic.
Windows
If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.
Note: If you need to modify the DSN or create other FHIR DSNs, you must use a system DSN and the bitness of the DSN must match your Oracle system. You can access and create 32-bit DSNs on a 64-bit system by opening the 32-bit ODBC Data Source Administrator from C:\Windows\SysWOW64\odbcad32.exe.
Linux
If you are installing the CData ODBC Driver for FHIR in a Linux environment, the driver installation predefines a system DSN. You can modify the DSN by editing the system data sources file (/etc/odbc.ini) and defining the required connection properties.
/etc/odbc.ini
[CData FHIR Source]
Driver = CData ODBC Driver for FHIR
Description = My Description
URL = http://test.fhir.org/r4b/
ConnectionType = Generic
ContentType = JSON
AuthScheme = None
For specific information on using these configuration files, please refer to the help documentation (installed and found online).
Set Connection Properties for Compatibility with Oracle
The driver provides several connection properties that streamline accessing FHIR data just as you would an Oracle database. Set the following properties when working with FHIR data in SQL*Plus and SQL Developer. For compatibility with Oracle, you will need to set the following connection properties, in addition to authentication and other required connection properties.
MapToWVarchar=False
Set this property to map string data types to SQL_VARCHAR instead of SQL_WVARCHAR. By default, the driver uses SQL_WVARCHAR to accommodate various international character sets. You can use this property to avoid the ORA-28528 Heterogeneous Services data type conversion error when the Unicode type is returned.
MaximumColumnSize=4000
Set this property to restrict the maximum column size to 4000 characters.
IncludeDualTable=True
Set this property to mock the Oracle DUAL table. SQL Developer uses this table to test the connection.
Linux Configuration
In Linux environments, Oracle uses UTF-8 to communicate with the unixODBC Driver manager, whereas the default driver encoding is UTF-16. To resolve this, open the file /opt/cdata/cdata-driver-for-fhir/lib/cdata.odbc.fhir.ini in a text editor and set the encoding.
cdata.odbc.fhir.ini
[Driver]
DriverManagerEncoding = UTF-8
Configure the ODBC Gateway, Oracle Net, and Oracle Database
Follow the procedure below to set up an ODBC gateway to FHIR data that enables you to query live FHIR data as an Oracle database.
-
Create the file initmyfhirdb.ora in the folder oracle-home-directory/hs/admin and add the following setting:
initmyfhirdb.ora
HS_FDS_CONNECT_INFO = "CData FHIR Sys"
-
Add an entry to the listener.ora file. This file is located in oracle-home-directory/NETWORK/admin.
If you are using the Database Gateway for ODBC, your listener.ora needs to have a SID_LIST_LISTENER entry that resembles the following:
listener.ora
SID_LIST_LISTENER = (SID_LIST = (SID_DESC = (SID_NAME = myfhirdb) (ORACLE_HOME = your-oracle-home) (PROGRAM = dg4odbc) ) )
If you are using Heterogeneous Services, your listener.ora needs to have a SID_LIST_LISTENER entry that resembles the following:
listener.ora
SID_LIST_LISTENER = (SID_LIST = (SID_DESC = (SID_NAME = myfhirdb) (ORACLE_HOME = your-oracle-home) (PROGRAM = hsodbc) ) )
-
Add the connect descriptor below in tnsnames.ora, located in oracle-home-directory/NETWORK/admin:
tnsnames.ora
myfhirdb = (DESCRIPTION= (ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1521)) (CONNECT_DATA=(SID=myfhirdb)) (HS=OK) )
- Restart the listener.
Test the configuration with the following command:
tnsping myfhirdb
-
Open SQL*Plus and create the database link with the command below:
CREATE DATABASE LINK myfhirdb CONNECT TO "user" IDENTIFIED BY "password" USING 'myfhirdb';
You can now execute queries in SQL*Plus like the one below (note the double quotation marks around the table name):
SELECT * from "Patient"@myfhirdb WHERE [address-city] = 'New York';