<http://schema.org/query-input>
"required name=search_term_string"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.codingforums.com/mysql/290311-running-db-filter-query-before-main-query.html?s=65eda7c57a3007a77b4a241aba2c1299>