10. The computer implemented method of claim 9 , wherein the document is an Extensible Markup Language (XML) document and the expression is an XPath expression.
10. The computer implemented method of claim 9 , wherein the document is an Extensible Markup Language (XML) document and the expression is an XPath expression. 11. The computer implemented method of claim 10 , wherein the mapping specification contains a data definition language statement with an option specifying the XPath expression.