XML provides support for combining data from multiple sources. In the process, however, it is possible to create confusion to tag disparate message elements with the same name.

For example, if you use the <Target> tag for data about quarterly sales goals in a Sales and Marketing application, and you use the <Target> tag to denote fiscal year revenue targets in a Finance application, errors can occur. Combining data from these two sources into one XML document, can cause naming collisions, or duplications, which may result in error messages or erroneous data. To avoid these collisions, use XML namespace declarations.

When constructing a request to BIRT iHub, use the namespaces the Actuate XML schema specifies. To use a namespace, first declare it in a header and then refer to it using the appropriate tag in the message. The following example shows how to declare two new namespaces by placing them in the SOAP envelope header:

These new namespaces define prefixes, fin and sales in the example above, as shorthand for data sources. Add the prefix to the appropriate tag name to indicate which data source to use. Use a simple prefix, separated from the tag name by a colon, as shown in the following example: