Writing a Custom Guide Database Loader

[This is preliminary documentation and subject to change.]

The Guide database stores information about what television programming is available through Broadcast Architecture applications. The information for the Guide database comes from different sources, such as the Internet and vertical blanking interval (VBI) transmissions. The database is a Microsoft® Jet database that can be accessed using Microsoft® Data Access Objects (DAO). To locate more information on DAO, see Further General Information.

To streamline access to the database, Broadcast Architecture uses loader programs. The two sample applications discussed in the following sections, Load and Download, show how to write custom database loader programs. To locate the source code for these sample applications, see Broadcast Architecture Sample Applications.

These sample loaders are written using Microsoft® Foundation Classes (MFC) and several libraries from Broadcast Architecture. Each sample has the same general structure and shows the important functions of a loader application. The sample called Download (Download.dll) reads television programming information from a text file and adds it to the Guide database. This sample shows how to write a full-featured loader. The sample called Load (Load.dll), a simplified example, gives an unobstructed view of how the loader functions for adding channels and shows to the Guide database work.

The following topics describe, in order, the tasks involved in loading data into the Program Guide:

1. Getting Data to the Client discusses possible sources of Program Guide data and how to get it to the broadcast client.
2. Making a Loader DLL describes the required features of a Guide database loader.
3. Using Guide Data Objects to Access the Database shows how to use functions in Broadcast Architecture to simplify loader development.
4. Entering Data shows specific examples of how to enter and edit records in the Guide database.
5. Removing Records Using Special Functions describes how to use special queries in the Guide database to perform housekeeping functions.
6. Installing and Running Your Loader shows how to use the Loadstub component and the Task Scheduler in the Microsoft® Windows® 98 operating system to run your loader.

For an overview on how to write a custom loader, see Writing a Custom Loader.