Defining the Necessary Data

Defining the data you will need is a key aspect of using an InfoPath 2003 form template. For very simple data sources, you won't need to spend long thinking about the necessary data; but as soon as you go beyond simple problems, this is time well spent. If you have defined the use cases well, you should have all the background information you need to work out which pieces of data you need.

If you are connecting to a relational database management system such as Microsoft Access or SQL Server 2000, which contains existing data, you must think carefully about the data you want to use before you start creating anything more than the simplest form templates.

Similarly, if you want to create a new database, make sure that you think carefully about your data needs. It is much more efficient to design an appropriate table structure the first time around than to spend time (perhaps using external staff) correcting faulty basic design decisions that could have been avoided by more careful initial thought.

RESOURCES

For more information about Access and SQL Server design issues, see Alison Balter's Mastering Microsoft Office Access 2003 (Sams Publishing, 2003) and Microsoft SQL Server 2000 Unleashed (Sams Publishing, 2002).

Secondary Data Sources

If your form template makes use of one or more secondary data sources, either from a relational database management system or an XML Web service, take a little time to identify and document your data needs.

If you are using a Web service as a secondary data source, make sure you consider whether the Web service might be discontinued. Have you informed the person running the Web service that you are depending on it? Have you ensured that you will be informed if it is changed?

Another practical issue to consider with secondary data sources is the possibility that users might want to complete a form offline. In that circumstance, it might be best to provide secondary data in the form of an XML file embedded in the form template, because secondary data derived from a relational database or XML Web service will be unavailable to the user . So, if a form is to be used offline, you must consider the trade-off between the advantages of dynamic secondary data sources, which can only be used when connected to the secondary data source, and the limitations of a fixed secondary data source (with its potential maintenance costs).

Minimizing Changes Late in the Process

InfoPath 2003 doesn't let you easily modify the form or its data source late in the implementation process. Therefore, InfoPath developers are well advised to avoid changes late in the form template development process. Of course, it isn't always possible to avoid this, because users aren't always clear about what they need.