A PostgreSQL Interface for Greenhouse Data

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

Connect to Greenhouse Data as a JDBC Data Source

To connect to Greenhouse 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.greenhouse.GreenhouseDriver

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

  You need an API key to connect to Greenhouse. To create an API key, follow the steps below:

  1. Click the Configure icon in the navigation bar and locate Dev Center on the left.
  2. Select API Credential Management.
  3. Click Create New API Key.
  • Set "API Type" to Harvest.
  • Set "Partner" to custom.
  • Optionally, provide a description.
  4. Proceed to Manage permissions and select the appropriate permissions based on the resources you want to access through the driver.
  5. Copy the created key and set APIKey to that value.

  Built-in Connection String Designer

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

  java -jar cdata.jdbc.greenhouse.jar

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

  A typical JDBC URL is below:

  jdbc:greenhouse:APIKey=YourAPIKey;

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 Greenhouse Data as a PostgreSQL Database

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

1. Log into your database.
2. Load the extension for the database: CREATE EXTENSION jdbc2_fdw;
3. Create a server object for Greenhouse: CREATE SERVER Greenhouse FOREIGN DATA WRAPPER jdbc2_fdw OPTIONS ( drivername 'cdata.jdbc.greenhouse.GreenhouseDriver', url 'jdbc:greenhouse:APIKey=YourAPIKey;', querytimeout '15', jarfile '/home/MyUser/CData/CData\ JDBC\ Driver\ for\ Salesforce MyDriverEdition/lib/cdata.jdbc.greenhouse.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 Greenhouse OPTIONS ( username 'admin', password 'test');
5. Create a foreign table in your local database: postgres=# CREATE FOREIGN TABLE applications ( applications_id text, applications_Id text, applications_CandidateId numeric) SERVER Greenhouse OPTIONS ( table_name 'applications');