Connect to Parquet Data in the Denodo Platform

Denodo Platform is a data virtualization product providing a single point of contact for enterprise database data. When paired with the CData JDBC Driver for Parquet, Denodo users can work with live Parquet data alongside other enterprise data sources. This article walks through creating a virtual data source for Parquet in the Denodo Virtual DataPort Administrator.

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

Create the Parquet Virtual Port

To connect to live Parquet data from Denodo, you need to copy the JDBC Driver JAR file to the external library directory for Denodo and create a new JDBC Data Source from the Virtual DataPort Administrator tool.

1. Download the CData JDBC Driver for Parquet installer, unzip the package, and run the JAR file to install the driver.
2. Copy the JAR File (and license file if it exists) from the installation location (typically C:\Program Files\CData\CData JDBC Driver for Parquet\lib\) to the Denodo external library directory (C:\Denodo\Denodo Platform\lib-external\jdbc-drivers\cdata-parquet-19).
3. Open the Denodo Virtual DataPort Administrator tool and navigate to the Server Explorer tab.
4. Right-click "admin" and select New -> Data source -> JDBC.
5. Configure the JDBC Connection:
   • Name: your choice, e.g.: parquet
   • Database adapter: Generic
   • Driver class path: C:\Denodo\Denodo Platform\lib-external\jdbc-drivers\cdata-parquet-19
   • Driver class: cdata.jdbc.parquet.ParquetDriver

   • Database URI: Set this to a JDBC URL using the necessary connection properties. For example,

     jdbc:parquet:URI=C:/folder/table.parquet;

     Information on creating the Database URI follows:

     Built-In Connection String Designer

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

     java -jar cdata.jdbc.parquet.jar

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

     Connect to your local Parquet file(s) by setting the URI connection property to the location of the Parquet file.

6. Click the "Test connection" button to confirm the configuration and click Save.

View Parquet Data in the VirtualPort Administrator Tool

After creating the data source, you can create a base view of Parquet data for use in the Denodo Platform.

1. Click the "Create base view" button in the newly created VirtualPort (admin.Parquet).
2. Expand the object tree and select the objects (tables) you wish to import.
3. Click the "Create selected" button to create views of the Parquet data.
   Optional: Click "Create associations from foreign keys" to define relationships between the objects.
4. With the view(s) created, navigate to a table (cdata_parquet_sampletable_1) in the Server Explorer and double-click the selected table.
5. In the new tab, click "Execution panel" to open a query panel.
6. Customize the query in the "Execute" tab or use the default:

   SELECT * FROM cdata_parquet_sampletable_1 CONTEXT ('i18n'='us_est', 'cache_wait_for_load'='true')
   

7. Click Execute to view the data.

With the base view created, you can now work with live Parquet data like you would any other data source in Denodo Platform, for example, querying Parquet in the Denodo Data Catalog.

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