DataBind Charts to AlloyDB Data

DataBinding facilitates two-way interaction with data through UI controls. Using the CData ADO.NET Provider for AlloyDB streamlines the process of binding AlloyDB data to Windows Forms and Web controls within Visual Studio. In this article, we will demonstrate using wizards to establish a binding between AlloyDB 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 AlloyDB, follow the steps outlined below using the Data Source Configuration Wizard. Within the wizard, you'll have the option to choose the specific AlloyDB 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. 👁 Add a data source to be bound to the chart.
   
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 AlloyDB Data Source.

   Below is a typical connection string:

   User=alloydb;Password=admin;Database=alloydb;Server=127.0.0.1;Port=5432

   The following connection properties are usually required in order to connect to AlloyDB.

   • Server: The host name or IP of the server hosting the AlloyDB database.
   • User: The user which will be used to authenticate with the AlloyDB server.
   • Password: The password which will be used to authenticate with the AlloyDB server.

   You can also optionally set the following:

   • Database: The database to connect to when connecting to the AlloyDB Server. If this is not set, the user's default database will be used.
   • Port: The port of the server hosting the AlloyDB database. This property is set to 5432 by default.

   Authenticating with Standard Authentication

   Standard authentication (using the user/password combination supplied earlier) is the default form of authentication.

   No further action is required to leverage Standard Authentication to connect.

   Authenticating with pg_hba.conf Auth Schemes

   There are additional methods of authentication available which must be enabled in the pg_hba.conf file on the AlloyDB server.

   Find instructions about authentication setup on the AlloyDB Server here.

   Authenticating with MD5 Authentication

   This authentication method must be enabled by setting the auth-method in the pg_hba.conf file to md5.

   Authenticating with SASL Authentication

   This authentication method must be enabled by setting the auth-method in the pg_hba.conf file to scram-sha-256.

   Authenticating with Kerberos

   The authentication with Kerberos is initiated by AlloyDB Server when the ∏ is trying to connect to it. You should set up Kerberos on the AlloyDB Server to activate this authentication method. Once you have Kerberos authentication set up on the AlloyDB Server, see the Kerberos section of the help documentation for details on how to authenticate with Kerberos.

   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.

   👁 Connection properties for the selected data source in the Add Connection dialog. (Salesforce is shown.)
   
5. Choose the database objects you want to work with. This example uses the Orders table. 👁 Select database objects. (Salesforce is shown.)
   

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 AlloyDB data. Run the chart to display the current data. 👁 The chart, filled with data at run time.

Code Walk-through

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

1. Connect to AlloyDB.
2. Create the AlloyDBDataAdapter 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:

AlloyDBConnection conn = new AlloyDBConnection("User=alloydb;Password=admin;Database=alloydb;Server=127.0.0.1;Port=5432");
AlloyDBCommand comm = new AlloyDBCommand("SELECT ShipName, ShipCity FROM Orders WHERE ShipCountry = 'USA'", conn);
AlloyDBDataAdapter da = new AlloyDBDataAdapter(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();