How to work with Exa Data in Apache Spark using SQL

Apache Spark is a fast and general engine for large-scale data processing. When paired with the CData JDBC Driver for Exa, Spark can work with live Exa data. This article describes how to connect to and query Exa data from a Spark shell.

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

Install the CData JDBC Driver for Exa

Download the CData JDBC Driver for Exa installer, unzip the package, and run the JAR file to install the driver.

Start a Spark Shell and Connect to Exa Data

1. Open a terminal and start the Spark shell with the CData JDBC Driver for Exa JAR file as the jars parameter:

   $ spark-shell --jars /CData/CData JDBC Driver for Exa/lib/cdata.jdbc.api.jar
   

2. With the shell running, you can connect to Exa with a JDBC URL and use the SQL Context load() function to read a table.

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

   Exa API Profile Settings

   Visit dashboard.exa.ai, sign in or create an account, and generate an API key from your API settings.

   Built-in Connection String Designer

   For assistance in constructing the JDBC URL, use the connection string designer built into the Exa 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.

   

   Configure the connection to Exa, using the connection string generated above.

   scala> val api_df = spark.sqlContext.read.format("jdbc").option("url", "jdbc:api:Profile=C:\profiles\Exa.apip;ProfileSettings='APIKey=your_api_key';").option("dbtable","Answer").option("driver","cdata.jdbc.api.APIDriver").load()
   

3. Once you connect and the data is loaded you will see the table schema displayed.

4. Register the Exa data as a temporary table:

   scala> api_df.registerTable("answer")

5. Perform custom SQL queries against the Data using commands like the one below:

   scala> api_df.sqlContext.sql("SELECT RequestId, Answer FROM Answer WHERE RequestId = my-request-id").collect.foreach(println)

   You will see the results displayed in the console, similar to the following:

   

Using the CData JDBC Driver for Exa in Apache Spark, you are able to perform fast and complex analytics on Exa data, combining the power and utility of Spark with your data. Download a free, 30 day trial of any of the hundreds of CData JDBC Drivers and get started today.