As soon as the output becomes available in the Output pane, you can validate it against the schema associated with it. For example, if the mapping transformation generates an XML file, it can be validated against the XML schema.
For XML files, you can specify the schema associated with the instance file in the Add Schema/DTD reference field of the Component Settings dialog box. The path specifies where the schema file referenced by the produced XML output is to be located. This ensures that the output instance can be validated when the mapping is executed. You can enter an http:// address in this field, an absolute or relative path. If you do not select the Add Schema/DTD reference field, the validation of the output file against the schema is not possible. If you select this check box but leave it empty, then the schema filename of the Component Settings dialog box is generated into the output, and the validation is done against it.
To validate the mapping output, do one of the following:
•Click (Validate Output) in the toolbar.
•Click Validate Output File in the Output menu.
Note that the Validate Output button and its corresponding menu command (Output | Validate Output File) are enabled only if the output file supports validation against a schema. The result of the validation is displayed in the Messages window.
If the validation is not successful, the message contains detailed information on the errors (see screenshot below).
The validation message contains a number of hyperlinks you can click for more detailed information:
•Clicking the file path opens the output of the transformation in the Output tab of MapForce.
•Clicking the <ElementName> link highlights the element in the Output tab.
•Clicking the icon opens the definition of the element in XMLSpy (if installed).
•Clicking the hyperlinks in the Details subsection (e.g., cvc-model-group) opens a description of the corresponding validation rule on the following website: https://www.w3.org/.