This section describes how to connect and start querying data from Tableau.
Add the CData JDBC Driver for HDFS
Note: Before starting Tableau on Windows, make sure that you have placed the .jar file in the C:\Program Files\Tableau\Drivers folder. Before starting Tableau on macOS, make sure that you have placed the .jar file in the ~/Library/Tableau/Drivers folder.
To add the driver .jar file:
- Start Tableau.
- Under To a Server, select More.
- Select Other Databases (JDBC).
- Enter the JDBC connection string in the URL field. See Building the JDBC URL for HDFS below for more information.
- Select Sign in.
Building the JDBC URL for HDFS
Connection strings provide information about a data source and how to connect to that data source. The driver comes with a connection string builder that makes it easier to create and manage the contents of connection strings.
After downloading and installing the driver, double-click the .jar file in the lib folder. You can also manually run the .jar file, as shown in the following examples.
java -jar 'C:\Program Files\CData\CData JDBC Driver for HDFS 2019\lib\cdata.jdbc.hdfs.jar'
Running the .jar file opens the Connection Properties dialog box. You can use this dialog box to build and test a connection string. Click Test Connection to test and validate the entered connection properties. Click Copy to Clipboard to copy the connection string for use within the application where the JDBC driver is being used. See the help documentation for more information about the connection string options.
Discover Schemas and Query Data
To query data:
- Select CData from the Database pull-down menu.
- Select Odata from the Schema pull-down menu.
- Drag the table onto the join area. You can include multiple tables.
- Select Update Now or Automatically Update. Update Now lets you preview the first 10,000 rows of the data source (or enter the number of rows you want to see in the Rows text box). Automatically Update automatically reflects the changes in the preview area.
- In the Connection menu, select the Live option, so that you skip loading a copy of the data into Tableau and instead work on real-time data.
- Click the tab for your worksheet. Columns are listed as Dimensions and Measures, depending on the data type.