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

Connect to EnterpriseDB Data as a JDBC Data Source

To connect to EnterpriseDB 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.enterprisedb.EnterpriseDBDriver
  

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

  The following connection properties are required in order to connect to data.

  • Server: The host name or IP of the server hosting the EnterpriseDB database.
  • Port: The port of the server hosting the EnterpriseDB database.

  You can also optionally set the following:

  • Database: The default database to connect to when connecting to the EnterpriseDB Server. If this is not set, the user's default database will be used.

  Connect Using Standard Authentication

  To authenticate using standard authentication, set the following:

  • User: The user which will be used to authenticate with the EnterpriseDB server.
  • Password: The password which will be used to authenticate with the EnterpriseDB server.

  Connect Using SSL Authentication

  You can leverage SSL authentication to connect to EnterpriseDB data via a secure session. Configure the following connection properties to connect to data:

  • SSLClientCert: Set this to the name of the certificate store for the client certificate. Used in the case of 2-way SSL, where truststore and keystore are kept on both the client and server machines.
  • SSLClientCertPassword: If a client certificate store is password-protected, set this value to the store's password.
  • SSLClientCertSubject: The subject of the TLS/SSL client certificate. Used to locate the certificate in the store.
  • SSLClientCertType: The certificate type of the client store.
  • SSLServerCert: The certificate to be accepted from the server.

  Built-in Connection String Designer

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

  java -jar cdata.jdbc.enterprisedb.jar
  

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

  👁 Using the built-in connection string designer to generate a JDBC URL (Salesforce is shown.)
  

  A typical JDBC URL is below:

  jdbc:enterprisedb:User=postgres;Password=admin;Database=postgres;Server=127.0.0.1;Port=5444
  

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 EnterpriseDB Data as a PostgreSQL Database

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

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

   CREATE EXTENSION jdbc2_fdw;
   

3. Create a server object for EnterpriseDB:

   CREATE SERVER EnterpriseDB 
   FOREIGN DATA WRAPPER jdbc2_fdw OPTIONS (
   drivername 'cdata.jdbc.enterprisedb.EnterpriseDBDriver',
   url 'jdbc:enterprisedb:User=postgres;Password=admin;Database=postgres;Server=127.0.0.1;Port=5444',
   querytimeout '15',
   jarfile '/home/MyUser/CData/CData\ JDBC\ Driver\ for\ Salesforce MyDriverEdition/lib/cdata.jdbc.enterprisedb.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 EnterpriseDB OPTIONS (
   username 'admin', 
   password 'test');
   

5. Create a foreign table in your local database:

   postgres=# CREATE FOREIGN TABLE orders (
   orders_id text,
   orders_ShipName text,
   orders_ShipCity numeric) 
   SERVER EnterpriseDB OPTIONS (
   table_name 'orders');
   

You can now execute read/write commands to EnterpriseDB:

postgres=# SELECT * FROM orders;