Input and output messages contain information about the structure of a web service. PowerCenter requires only output messages for a web service source definition. A web service source might require input values. Input messages are optional for web service sources. PowerCenter requires only input messages for a web service target definition. It requires both input and output messages for a Web Services Consumer transformation. If the web service operation lacks the necessary input or output messages, the Designer does not let you import that operation.

The following table lists PowerCenter requirements for input and output messages: