Build a PostgreSQL Interface for Carbone Data using the CData JDBC Driver

There are a vast number of PostgreSQL clients available on the Internet. From standard Drivers to BI and Analytics tools, PostgreSQL is a popular interface for data access. Using our JDBC Drivers, you can now create PostgreSQL entry-points that you can connect to from any standard client.

To access Carbone data as a PostgreSQL database, use the CData JDBC Driver for Carbone and a JDBC foreign data wrapper (FDW). In this article, we compile the FDW, install it, and query Carbone data from PostgreSQL Server.

Connect to Carbone Data as a JDBC Data Source

To connect to Carbone as a JDBC data source, you will need the following:

• Driver JAR path: The JAR is located in the lib subfolder of the installation directory.

• Driver class:

  
  cdata.jdbc.api.APIDriver
  

• JDBC URL: The URL must start with "jdbc:api:" and can include any of the connection properties in name-value pairs separated with semicolons.

  Start by setting the Profile connection property to the location of the Carbone Profile on disk (e.g. C:\profiles\Carbone.apip). Next, set the ProfileSettings connection property to the connection string for Carbone (see below).

  Carbone API Profile Settings

  Carbone uses API key authentication via a Bearer token in the Authorization header. To obtain an API key:

  1. Log in to your Carbone account at https://account.carbone.io
  2. Copy the API key shown on the account home page

  After obtaining your API key, set the following connection properties:

  • AuthScheme: Set this to APIKey.
  • APIKey: Set this to your Carbone API key (Bearer token).
  • CarboneVersion: (Optional) The major version of the Carbone API to target via the carbone-version request header. Defaults to 5. Accepted values: 5, 4, 3, staging.

  Built-in Connection String Designer

  For assistance in constructing the JDBC URL, use the connection string designer built into the Carbone JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.

  
  java -jar cdata.jdbc.api.jar
  

  Fill in the connection properties and copy the connection string to the clipboard.

  

  A typical JDBC URL is below:

  
  jdbc:api:Profile=C:\profiles\Carbone.apip;AuthScheme=APIKey;APIKey=your_api_key;
  

Build the JDBC Foreign Data Wrapper

The Foreign Data Wrapper can be installed as an extension to PostgreSQL, without recompiling PostgreSQL. The jdbc2_fdw extension is used as an example (downloadable here).

1. Add a symlink from the shared object for your version of the JRE to /usr/lib/libjvm.so. For example:

   
   ln -s /usr/lib/jvm/java-6-openjdk/jre/lib/amd64/server/libjvm.so /usr/lib/libjvm.so
   

2. Start the build:

   
   make install USE_PGXS=1
   

Query Carbone Data as a PostgreSQL Database

After you have installed the extension, follow the steps below to start executing queries to Carbone data:

1. Log into your database.
2. Load the extension for the database:

   
   CREATE EXTENSION jdbc2_fdw;
   

3. Create a server object for Carbone:

   
   CREATE SERVER API 
   FOREIGN DATA WRAPPER jdbc2_fdw OPTIONS (
   drivername 'cdata.jdbc.api.APIDriver',
   url 'jdbc:api:Profile=C:\profiles\Carbone.apip;AuthScheme=APIKey;APIKey=your_api_key;',
   querytimeout '15',
   jarfile '/home/MyUser/CData/CData\ JDBC\ Driver\ for\ Salesforce MyDriverEdition/lib/cdata.jdbc.api.jar'); 
   

4. Create a user mapping for the username and password of a user known to the MySQL daemon.

   
   CREATE USER MAPPING for postgres SERVER API OPTIONS (
   username 'admin', 
   password 'test');
   

5. Create a foreign table in your local database:

   
   postgres=# CREATE FOREIGN TABLE templates (
   templates_id text,
   templates_Id text,
   templates_Name numeric) 
   SERVER API OPTIONS (
   table_name 'templates');
   

postgres=# SELECT * FROM templates;