How to work with Demio 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 Demio, Spark can work with live Demio data. This article describes how to connect to and query Demio data from a Spark shell.

The CData JDBC Driver offers unmatched performance for interacting with live Demio data due to optimized data processing built into the driver. When you issue complex SQL queries to Demio, the driver pushes supported SQL operations, like filters and aggregations, directly to Demio 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 Demio data using native data types.

Install the CData JDBC Driver for Demio

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

Start a Spark Shell and Connect to Demio Data

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

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

2. With the shell running, you can connect to Demio 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 Demio Profile on disk (e.g. C:\profiles\Demio.apip). Next, set the ProfileSettings connection property to the connection string for Demio (see below).

   Demio API Profile Settings

   Navigate to Account Settings > API in your Demio account (Owner access required) to obtain your API Key and API Secret.

   Built-in Connection String Designer

   For assistance in constructing the JDBC URL, use the connection string designer built into the Demio 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 Demio, using the connection string generated above.

   scala> val api_df = spark.sqlContext.read.format("jdbc").option("url", "jdbc:api:Profile=C:\profiles\Demio.apip;ProfileSettings='APIKey=your_api_key;APISecret=your_api_secret';").option("dbtable","Event").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 Demio data as a temporary table:

   scala> api_df.registerTable("event")

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

   scala> api_df.sqlContext.sql("SELECT Id, Name FROM Event WHERE Automated = true").collect.foreach(println)

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

   

Using the CData JDBC Driver for Demio in Apache Spark, you are able to perform fast and complex analytics on Demio 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.