Validate HDFS Data with QuerySurge

QuerySurge is a smart data testing solution that automates data validation and testing. When paired with the CData JDBC Driver for HDFS, QuerySurge can work with live HDFS data. This article explains how to connect to HDFS data from QuerySurge.

With built-in optimized data processing, the CData JDBC Driver offers unmatched performance for interacting with live HDFS data. When you issue complex SQL queries to HDFS, the driver pushes supported SQL operations, like filters and aggregations, directly to HDFS and utilizes the embedded SQL engine to process unsupported operations client-side (often SQL functions and JOIN operations). Its built-in dynamic metadata querying allows you to work with and analyze HDFS data using native data types.

Connecting to HDFS Data in QuerySurge

To connect to live HDFS data from QuerySurge, you need to deploy the JDBC Driver JAR file to your QuerySurge Agent(s) and add a new connection from the QuerySurge Admin view.

Deploy the JDBC Driver

1. Download the CData JDBC Driver for HDFS installer, unzip the package, and run the JAR file to install the driver.
2. Once the driver is installed, stop the Agent Service.
3. Copy the JAR File (and license file if it exists) from the installation location (typically C:\Program Files\CData\CData JDBC Driver for HDFS\lib\) to your Agent(s) (QuerySurge_install_dir\agent\jdbc).
4. Restart the Agent Service.

For more information on deploying JDBC drivers for QuerySurge, refer to the QuerySurge Knowledge Base.

Configure a New Connection to HDFS

1. Log into QuerySurge and navigate to the Admin view.
2. Click Configuration -> Connections in the Administration Tree.
3. Click Add to create a new connection.
4. In the QuerySurge Connection Wizard, click Next. 👁 Creating a new connection
   
5. Name the connection (e.g. CData JDBC Connection to HDFS).
6. Set the Data Source to "All Other JDBC Connections (Connection Extensibility)" and click Next. 👁 Naming the connection and choosing a Data Source
   
7. Set the Driver Class to cdata.jdbc.hdfs.HDFSDriver and click Next. 👁 Setting the Driver Class
   

8. Set the Connection URL using the necessary connection properties to authenticate with HDFS. Your Connection URL will look something like the following:

   jdbc:hdfs:Host=sandbox-hdp.hortonworks.com;Port=50070;Path=/user/root;User=root;

   Built-in Connection String Designer

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

   java -jar cdata.jdbc.hdfs.jar
   	

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

   In order to authenticate, set the following connection properties:

   • Host: Set this value to the host of your HDFS installation.
   • Port: Set this value to the port of your HDFS installation. Default port: 50070
   👁 Using the built-in connection string designer to generate a JDBC URL (Salesforce is shown.)
   
9. Set the Test Query to enable the Test Connection button for the Connection (e.g. SELECT * FROM Files LIMIT 1) and click Next. 👁 Setting the Connection URL and Test Query (NetSuite is shown)
   
10. Click Test Connection to ensure the connection is configured properly and click Save to add the connection.

Once the connection is added, you can write SQL queries against your HDFS data in QuerySurge.

Compare HDFS Data Queries with a QueryPair

With the connection configured, you can follow the steps below to compare querying HDFS data with a QueryPair.

1. Select "Design Library" from the Design Menu
2. Click QueryPairs under QuerySurge Design
3. Click "Create New QueryPair"
4. Name the QueryPair and click Save
5. In either the Source or Target panes, select the connection created above (select the same connection to query HDFS twice or another connection to perform a comparison)
6. Write queries in the Editor for each pane, e.g. SELECT * FROM Files 👁 Setting the Connection URL and Test Query (NetSuite is shown)
   
7. Click the "Design-Time Run" tab to execute the queries
8. When the query execution is finished, click "View Query Results" to see the HDFS data returned by the query 👁 Setting the Connection URL and Test Query (NetSuite is shown)
   

Download a free, 30-day trial of the CData JDBC Driver for HDFS and start working with your live HDFS data in QuerySurge. Reach out to our Support Team if you have any questions.