This document describes how to access Cloudera from the Denodo Platform.
Cloudera Impala is a SQL engine provided with the Cloudera Hadoop distribution that provides fast interactive SQL queries directly on Hadoop data stored in HDFS or HBase. Impala provides a JDBC driver which Denodo can readily use to connect.
Connecting to Cloudera from Denodo
- In the Denodo Design Studio, you can create a new data source by clicking on the left panel and then select “New -> Data Source -> JDBC”. After clicking, a new tab opens to create a JDBC connection
- To create a connection to your impala instance, fill all required fields:
- Name: ds_impala
- Database adapter: Impala 2.3
- Database URI: Use a connection string in the form of: jdbc:impala://<server>:<port>/<schema>
For example: jdbc:impala://localhost:21050/tpcds
- Username: Enter the username to connect to Impala.
- Password: Enter the appropriate password.
- Once the details are filled, click on “Test Connection” and if the connection is successful, click on “Save”.
- If a message is received which states that the driver is missing, please follow the instructions in Supported JDBC Data sources. The link contains information about where to download the JDBC driver for Impala. The upload can be done following Uploading a JDBC Driver using the Virtual DataPort Administration Tool
- Once the data source is created, you can create base views for that particular source. In order to do that, click on the "Create Base View" option.
- The Tool will then display a tree with the schemas of the database. Click on any schema to inspect its tables and their fields. To search a view or a schema, type its name in the “search” box located at the top. In the text box “Prefix view names with:” on the bottom of the screen enter “bv_” for following Denodo best practice naming conventions as we are creating base views
- Incorporate the tables into the Denodo virtual schema by checking the box near the data source elements you want to import and then click “Create selected”.
- When the importing process is finished, the new views are displayed.
- Now, the base views are ready for the execution and to be combined with the rest of the sources.
Virtual DataPort Administration Guide: JDBC Sources
Virtual DataPort Administration Guide: Uploading a JDBC Driver