DataBind Controls to SAS Data Sets Data in C++Builder

The CData ODBC driver for SAS Data Sets makes it easy to integrate connectivity to live SAS Data Sets data with standard data access components in C++Builder. This article shows how to create a simple visual component library (VCL) application in C++Builder that connects to SAS Data Sets data, executes queries, and displays the results in a grid. An additional section shows how to use FireDAC components to execute commands from code.

Create a Connection to SAS Data Sets Data

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.

Set the following connection properties to connect to your SAS DataSet files:

Connecting to Local Files

• Set the Connection Type to "Local." Local files support SELECT, INSERT, and DELETE commands.
• Set the URI to a folder containing SAS files, e.g. C:\PATH\TO\FOLDER\.

Connecting to Cloud-Hosted SAS DataSet Files

While the driver is capable of pulling data from SAS DataSet files hosted on a variety of cloud data stores, INSERT, UPDATE, and DELETE are not supported outside of local files in this driver.

Set the Connection Type to the service hosting your SAS DataSet files. A unique prefix at the beginning of the URI connection property is used to identify the cloud data store and the remainder of the path is a relative path to the desired folder (one table per file) or single file (a single table). For more information, refer to the Getting Started section of the Help documentation.

You can then follow the steps below to use the Data Explorer to create a FireDAC connection to SAS Data Sets.

1. In a new VCL Forms application, expand the FireDAC node in the Data Explorer.
2. Right-click the ODBC Data Source node in the Data Explorer.
3. Click Add New Connection.
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 SAS Data Sets.

👁 A FireDAC connection to the ODBC data source. (Salesforce is shown.)

Create VCL Applications with Connectivity to SAS Data Sets Data

Follow the procedure below to start querying SAS Data Sets data from a simple VCL application that displays the results of a query in a grid.

1. Drop a TFDConnection component onto the form and set the following properties:

   • ConnectionDefName: Select the FireDAC connection to SAS Data Sets.
   • Connected: Select True from the menu and, in the dialog that appears, enter your credentials.

2. Drop a TFDQuery component onto the form and set the properties below:

   • Connection: Set this property to the TFDConnection component, if this component is not already specified.

   • SQL: Click the button in the SQL property and enter a query. For example:

     SELECT name, borough FROM restaurants WHERE cuisine = 'American'
     

   • Active: Set this property to true.

3. Drop a TDataSource component onto the form and set the following property:

   • DataSet: In the menu for this property, select the name of the TFDQuery component.

4. Drop a TDBGrid control onto the form and set the following property:

   • DataSource: Select the name of the TDataSource.
5. Drop a TFDGUIxWaitCursor onto the form — this is required to avoid a run-time error.

👁 Components in FireDAC used to databind an editable grid to the data source. (Salesforce is shown.)

Execute Commands to SAS Data Sets with FireDAC Components

You can use the TFDConnection and TFQuery components to execute queries to SAS Data Sets data. This section provides SAS Data Sets-specific examples of executing queries with the TFQuery component.

Connect to SAS Data Sets Data

To connect to the data source, set the Connected property of the TFDConnection component to true. You can set the same properties from code:

FDConnection1->ConnectionDefName = "CData SAS Data Sets ODBC Source";
FDConnection1->Connected = true;

To connect the TFDQuery component to SAS Data Sets data, set the Connection property of the component. When a TFDQuery component is added at design time, its Connection property is automatically set to point to a TFDConnection on the form, as in the application above.

Create Parameterized Queries

To create a parameterized query, use the following syntax below:

FDQuery1->SQL->Text = "select * from restaurants where cuisine = :cuisine";
FDQuery1->ParamByName("cuisine")->AsString = "American";
FDQuery1->Open();

The example above binds a string-type input parameter by name and then opens the dataset that results.

Prepare the Statement

Preparing statements is costly in system resources and time. The connection must be active and open while a statement is prepared. By default, FireDAC prepares the query to avoid recompiling the same query over and over. To disable statement preparation, set ResourceOptions.DirectExecute to True; for example, when you need to execute a query only once.

Execute a Query

To execute a query that returns a result set, such as a select query, use the Open method. The Open method executes the query, returns the result set, and opens it. The Open method will return an error if the query does not produce a result set.

FDQuery1->SQL->Text = "select * from restaurants where cuisine = :cuisine";
FDQuery1->ParamByName("cuisine")->AsString = "American";
FDQuery1->Open();

To execute a query that does not return a result set, use the ExecSQL method. The ExecSQL method will return an error if the query returns a result set. To retrieve the count of affected rows use the TFD.RowsAffected property.

FDQuery1->SQL->Text = "delete from restaurants where Id = :Id";
FDQuery1->Params->Items[0]->AsString = "x12345";
FDQuery1->ExecSQL();
AnsiString i = FDQuery1->RowsAffected;
ShowMessage("Rows affected: " + i);

Related Articles

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

• DataBind Controls to SAS Data Sets Data in Delphi
• Viewing SAS Data Sets Data in RAD Studio Data Explorer
• Build a Simple VCL Application for SAS Data Sets Data