DataBind Charts to Lakebase Data

DataBinding facilitates two-way interaction with data through UI controls. Using the CData ADO.NET Provider for Lakebase streamlines the process of binding Lakebase data to Windows Forms and Web controls within Visual Studio. In this article, we will demonstrate using wizards to establish a binding between Lakebase data and a chart that dynamically updates. Additionally, the code walk-through section will guide you through the creation of a chart using just 10 lines of code.

Binding Data to a Chart

DataBinding to a Chart consists of three steps: Instantiate the control, configure the data source, and databind.

Configure the Connection and Select Database Objects

To create a chart control and establish a connection to Lakebase, follow the steps outlined below using the Data Source Configuration Wizard. Within the wizard, you'll have the option to choose the specific Lakebase entities you wish to bind to.

1. In a Windows Forms project, drag and drop a Chart control from the toolbox to the form. In the Data section of the Chart properties, select DataSource and then select Add Project Data Source from the menu.
2. In the Data Source Configuration Wizard that appears, select Database -> Dataset.
3. In the Choose Your Data Connection step, click New Connection.

4. In the Add Connection dialog, click Change to select the CData Lakebase Data Source.

   Below is a typical connection string:

   DatabricksInstance=lakebase;Server=127.0.0.1;Port=5432;Database=my_database;InitiateOAuth=GETANDREFRESH;

   To connect to Databricks Lakebase, start by setting the following properties:
   • DatabricksInstance: The Databricks instance or server hostname, provided in the format instance-abcdef12-3456-7890-abcd-abcdef123456.database.cloud.databricks.com.
   • Server: The host name or IP address of the server hosting the Lakebase database.
   • Port (optional): The port of the server hosting the Lakebase database, set to 5432 by default.
   • Database (optional): The database to connect to after authenticating to the Lakebase Server, set to the authenticating user's default database by default.

   OAuth Client Authentication

   To authenicate using OAuth client credentials, you need to configure an OAuth client in your service principal. In short, you need to do the following:

   1. Create and configure a new service principal
   2. Assign permissions to the service principal
   3. Create an OAuth secret for the service principal

   For more information, refer to the Setting Up OAuthClient Authentication section in the Help documentation.

   OAuth PKCE Authentication

   To authenticate using the OAuth code type with PKCE (Proof Key for Code Exchange), set the following properties:

   • AuthScheme: OAuthPKCE.
   • User: The authenticating user's user ID.

   For more information, refer to the Help documentation.

   When you configure the connection, you may also want to set the Max Rows connection property. This will limit the number of rows returned, which is especially helpful for improving performance when designing reports and visualizations.

   
5. Choose the database objects you want to work with. This example uses the Orders table.

DataBind

After adding the data source and selecting database objects, you can bind the objects to the chart. This example assigns the x-axis to ShipName and the y-axis to ShipCity.

1. In the Chart properties, click the button in the Series property to open the Series Collection Editor.
2. In the Series properties, select the columns you want for the x- and y-axes: Select columns from the menu in the XValueMember and YValueMember properties.

The chart is now databound to the Lakebase data. Run the chart to display the current data.

Code Walk-through

DataBinding to Lakebase data requires only a few lines of code and can be completed in three easy steps.

1. Connect to Lakebase.
2. Create the LakebaseDataAdapter to execute the query and create a DataSet to be filled with its results.
3. DataBind the result set to the chart.

Below is the complete code:

LakebaseConnection conn = new LakebaseConnection("DatabricksInstance=lakebase;Server=127.0.0.1;Port=5432;Database=my_database;InitiateOAuth=GETANDREFRESH;");
LakebaseCommand comm = new LakebaseCommand("SELECT ShipName, ShipCity FROM Orders WHERE ShipCountry = 'USA'", conn);
LakebaseDataAdapter da = new LakebaseDataAdapter(comm);
DataSet dataset = new DataSet();
da.Fill(dataset);

chart1.DataSource = dataset;  
chart1.Series[0].XValueMember = "ShipName";
chart1.Series[0].YValueMembers = "ShipCity";
// Insert code for additional chart formatting here.
chart1.DataBind();