You can edit the web service source or target definition based on how you create it:
Source or target definition imported from a WSDL.
If you import the web service source or target definition from a WSDL, you can edit the source or target definition in the WSDL workspace. You can use the WSDL workspace to add, modify, or delete views in the source or target definition.
You can view the definition and edit some properties in the Designer workspace.
Source or target definition created from a relational or flat file source and target.
If you create a web service source or target definition based on a relational or flat file target, you can edit the columns in the Designer workspace.
You can view the source or target definition in the WSDL workspace. You cannot edit the source or target definition in the WSDL workspace.
You can edit web service sources and targets created in PowerCenter version 9.0.1 or later. To avoid errors when you run web service workflows, do not edit web service sources and targets upgraded from previous versions. To update a web service source or target from previous versions of PowerCenter, re-create the source or target in PowerCenter version 9.0.1 or later.