How to Generate SQL Command Schemas for the CData BizTalk Adapter for REST

This article will show how to generate a schema to process REST data retrieved using the CData BizTalk Adapter. You will generate a schema for a SELECT command.

This guide shows how to use the CData BizTalk Adapter for REST to execute SQL commands to REST.

Add the Adapter for REST to Your Project

Follow the steps below to add the adapter to a BizTalk Server project.

1. If you have not already done so, create a new BizTalk Server project in Visual Studio.
2. Right-click on the project in the Solution Explorer and click Add -> Add Generated Items.
3. Select Add Adapter Metadata in the resulting dialog box.
4. In the resulting Add Adapter wizard, select the adapter from the list.
5. In the Port menu, leave the selection blank. You can also select a receive location or send port that has the adapter configured as its transport type.

Generate a Schema for an SQL Command

After you select the adapter in the Add Adapter wizard, the Schema wizard is displayed. Follow the steps below to configure connection properties and retrieve the metadata for the results of the command.

1. In the Connection String page, enter authentication credentials and other connection properties, if you did not select an adapter that you have already configured in your BizTalk application. Below is a typical connection string: DataModel=Relational;URI=C:/people.xml;Format=XML;

   See the Getting Started chapter in the data provider documentation to authenticate to your data source: The data provider models REST APIs as bidirectional database tables and XML/JSON files as read-only views (local files, files stored on popular cloud services, and FTP servers). The major authentication schemes are supported, including HTTP Basic, Digest, NTLM, OAuth, and FTP. See the Getting Started chapter in the data provider documentation for authentication guides.

   After setting the URI and providing any authentication values, set Format to "XML" or "JSON" and set DataModel to more closely match the data representation to the structure of your data.

   The DataModel property is the controlling property over how your data is represented into tables and toggles the following basic configurations.

   • Document (default): Model a top-level, document view of your REST data. The data provider returns nested elements as aggregates of data.
   • FlattenedDocuments: Implicitly join nested documents and their parents into a single table.
   • Relational: Return individual, related tables from hierarchical data. The tables contain a primary key and a foreign key that links to the parent document.

   See the Modeling REST Data chapter for more information on configuring the relational representation. You will also find the sample data used in the following examples. The data includes entries for people, the cars they own, and various maintenance services performed on those cars.

2. In the General Options section on the next page, Schema Information, select Send Port or Receive Location, depending on the adapter configuration.
3. If you want to generate the schema for the entire result set, select the Single Message option in the Message Mode menu. If you want to generate one schema for each row in the result set, select the Message Per Row option and confirm that the root element of the message is 'row'.
4. In the Command Type menu, select SQL Command.

5. In the SQL Command Text box on the Statement Information page, enter an SQL command. (If you have configured a receive location or send port, the SQL command you configured is entered in the box.) This example uses the query below:

   SELECT [people].[personal.age] AS age, [people].[personal.gender] AS gender, [people].[personal.name.first] AS first_name, [people].[personal.name.last] AS last_name, [vehicles].[model], FROM [people] JOIN [vehicles] ON [people].[_id] = [vehicles].[people_id]

6. Confirm the settings in the summary displayed by the wizard and click Finish to generate the schema.xsd file.

Processing Schemas

To use schemas in a simple BizTalk application, see the tutorial.