Viewing HDFS Data in RAD Studio Data Explorer

Embarcadero RAD Studio provides a development environment for Delphi and C++Builder applications. With the CData ODBC Driver for HDFS, you gain access to live HDFS data within RAD Studio, abstracting the data into tables, views, and stored procedures that can be used to both retrieve HDFS data. This article will walk through connecting to HDFS using the Data Explorer.

Configure a Connection to HDFS

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.

In order to authenticate, set the following connection properties:

• Host: Set this value to the host of your HDFS installation.
• Port: Set this value to the port of your HDFS installation. Default port: 50070

Connecting to HDFS Data Using Data Explorer

You can create a simple application for displaying HDFS data by utilizing the CData FireDAC Components for HDFS and a new VCL Forms Application:

1. Open the Data Explorer in RAD Studio and expand FireDAC.
2. Right-click the ODBC Data Source node in the Data Explorer.
3. Click Add New Connection. 👁 Adding a New Connection. (Salesforce is shown.)
   
4. Enter a name for the connection.
5. In the FireDAC Connection Editor that appears, set the DataSource property to the name of the ODBC DSN for HDFS. 👁 Setting the Connection Parameters. (Salesforce is shown.)
   
6. Back in the Data Explorer, expand the views for the connection.

7. Create a new VCL Forms application and drag a view (for example: Files) onto the form.

   👁 Placing the View on the Form. (Salesforce is shown.)
   
8. Select the FilesView object on the form and set the Active property to true.

9. Right-click on the object, bind visually, and link everything (*) to a new control (TStringGrid).

   👁 Visually Binding the View. (Salesforce is shown.)
   

10. Arrange the TStringGrid on the form and run the application to see the Files data.

    👁 The View data on a Form. (Salesforce is shown.)
    

Related Articles

Below you can find other articles for using the CData ODBC Driver with RAD Studio, Delphi, and C++ Builder.

• DataBind Controls to HDFS Data in C++Builder
• DataBind Controls to HDFS Data in Delphi
• Build a Simple VCL Application for HDFS Data