Using the Cloudera JDBC Connector (recommended)

You download and install the Cloudera JDBC 2.5 connector on any Linux, Windows, or Mac system where you intend to run JDBC-enabled applications. From the Cloudera Connectors download page, you choose the appropriate protocol (JDBC or ODBC) and target product (Impala or Hive). The ease of downloading and installing on a wide variety of systems makes this connector a convenient choice for organizations with heterogeneous environments.

Using the Hive JDBC Driver

You install the Hive JDBC driver (hive-jdbc package) through the Linux package manager, on hosts within the CDH cluster. The driver consists of several Java JAR files. The same driver can be used by Impala and Hive.

To get the JAR files, install the Hive JDBC driver on each host in the cluster that will run JDBC applications. Follow the instructions for Installing Cloudera JDBC and ODBC Drivers on Clients in CDH.

  Note: The latest JDBC driver, corresponding to Hive 0.13, provides substantial performance improvements for Impala queries that return large result sets. Impala 2.0 and later are compatible with the Hive 0.13 driver. If you already have an older JDBC driver installed, and are running Impala 2.0 or higher, consider upgrading to the latest Hive JDBC driver for best performance with JDBC applications.

If you are using JDBC-enabled applications on hosts outside the CDH cluster, you cannot use the CDH install procedure on the non-CDH hosts. Install the JDBC driver on at least one CDH host using the preceding procedure. Then download the JAR files to each client machine that will use JDBC with Impala:

commons-logging-X.X.X.jar
  hadoop-common.jar
  hive-common-X.XX.X-cdhX.X.X.jar
  hive-jdbc-X.XX.X-cdhX.X.X.jar
  hive-metastore-X.XX.X-cdhX.X.X.jar
  hive-service-X.XX.X-cdhX.X.X.jar
  httpclient-X.X.X.jar
  httpcore-X.X.X.jar
  libfb303-X.X.X.jar
  libthrift-X.X.X.jar
  log4j-X.X.XX.jar
  slf4j-api-X.X.X.jar
  slf4j-logXjXX-X.X.X.jar
  

To enable JDBC support for Impala on the system where you run the JDBC application:

1. Download the JAR files listed above to each client machine.
     Note: For Maven users, see this sample github page for an example of the dependencies you could add to a pom file instead of downloading the individual JARs.
2. Store the JAR files in a location of your choosing, ideally a directory already referenced in your CLASSPATH setting. For example:
   • On Linux, you might use a location such as /opt/jars/.
   • On Windows, you might use a subdirectory underneath C:\Program Files.
3. To successfully load the Impala JDBC driver, client programs must be able to locate the associated JAR files. This often means setting the CLASSPATH for the client process to include the JARs. Consult the documentation for your JDBC client for more details on how to install new JDBC drivers, but some examples of how to set CLASSPATH variables include:
   • On Linux, if you extracted the JARs to /opt/jars/, you might issue the following command to prepend the JAR files path to an existing classpath:

     export CLASSPATH=/opt/jars/*.jar:$CLASSPATH

   • On Windows, use the System Properties control panel item to modify the Environment Variables for your system. Modify the environment variables to include the path to which you extracted the files.
       Note: If the existing CLASSPATH on your client machine refers to some older version of the Hive JARs, ensure that the new JARs are the first ones listed. Either put the new JAR files earlier in the listings, or delete the other references to Hive JAR files.

Using the Cloudera JDBC Connector (recommended)

Depending on the level of the JDBC API your application is targeting, you can use the following fully-qualified class names (FQCNs):

• com.cloudera.impala.jdbc41.Driver
• com.cloudera.impala.jdbc41.DataSource

• com.cloudera.impala.jdbc4.Driver
• com.cloudera.impala.jdbc4.DataSource

• com.cloudera.impala.jdbc3.Driver
• com.cloudera.impala.jdbc3.DataSource

The connection string has the following format:

jdbc:impala://Host:Port[/Schema];Property1=Value;Property2=Value;...

The port value is typically 21050 for Impala.

For full details about the classes and the connection string (especially the property values available for the connection string), download the appropriate driver documentation for your platform from the Impala JDBC Connector download page.

Using the Hive JDBC Driver

For example, with the Hive JDBC driver, the class name is org.apache.hive.jdbc.HiveDriver. Once you have configured Impala to work with JDBC, you can establish connections between the two. To do so for a cluster that does not use Kerberos authentication, use a connection string of the form jdbc:hive2://host:port/;auth=noSasl. For example, you might use:

jdbc:hive2://myhost.example.com:21050/;auth=noSasl

To connect to an instance of Impala that requires Kerberos authentication, use a connection string of the form jdbc:hive2://host:port/;principal=principal_name. The principal must be the same user principal you used when starting Impala. For example, you might use:

jdbc:hive2://myhost.example.com:21050/;principal=impala/myhost.example.com@H2.EXAMPLE.COM

To connect to an instance of Impala that requires LDAP authentication, use a connection string of the form jdbc:hive2://host:port/db_name;user=ldap_userid;password=ldap_password. For example, you might use:

jdbc:hive2://myhost.example.com:21050/test_db;user=fred;password=xyz123

  Note:

Prior to CDH 5.7 / Impala 2.5, the Hive JDBC driver did not support connections that use both Kerberos authentication and SSL encryption. If your cluster is running an older release that has this restriction, to use both of these security features with Impala through a JDBC application, use the Cloudera JDBC Connector as the JDBC driver.