XQuery parameter binding changed in 2.18

[jkorab]

Now need to bind the headers as strings and cast to an int:

.transform(xquery("declare variable $in.headers.myParamValue as xs:string external; {for $x in /bookstore/book where $x/price>($in.headers.myParamValue cast as xs:integer) order by $x/title return $x/title}"));