One of the essential features of the XML Schema language are identity constraints (key / keyref / unique), which are typically used to model relational database concepts in XML Schema. Up until now, however, editing identity constraints was typically a very cumbersome task because it mostly needed to be done by hand - either in text view or through the properties pages.
In XMLSpy 2009 we've now addressed identity constraints editing with a powerful new way to both visualize the constraints and underlying relationships, as well as a graphical means to edit them in the visual XML Schema editor:
Identity constraints are now indicated by green lines, informative icons, and mouse-over messages in the Content Model View. A right-click menu allows you to easily add new relationships and specify field and selector values by typing them manually, using drop-down entry helpers, or by simply dragging and dropping the desired nodes.
This is a "must have" feature for anybody involved with XML Schema design or relational database and XML work. Click here to try it out for free for 30 days....