XML Validation

When you define your Data Model, you better enforce as many restrictions as you can on your data.... too many times a request fails mysteriously because the input data fails to comply to business specifications, and the earlier you catch this - the better.

Here are the validations available in the XSD
http://www.w3schools.com/schema/schema_facets.asp


For more complex validation (like: is element E1 value is A, then element E2 can only be X or Z), you should use Schematron:

Here some links to Schematron

http://www.dpawson.co.uk/schematron/index.html
http://www.xfront.com/schematron/index.html
http://www.codeproject.com/KB/XML/schematron_started.aspx
http://www.docstoc.com/docs/2134799/Schematron-Editor-Tutorial

I am not aware of how much Schematron is supported in a Oracle "SOA Suite" project.... I shall investigate...