Apparatus and method for handling a LET binding

摘要

An apparatus and method for handling a LET binding used in a WHERE clause of an XQuery FLWOR expression during an XML pivot join procedure. The disclosed apparatus and method enable an XML pivot join procedure to accurately process a query and return one or more qualifying documents. A logical expression within the WHERE clause is identified. Next steps of the logical expression are separated by logical operators. The LET binding is incorporated with each next step. The XQuery FLWOR expression is rewritten using the incorporations along with a FOR binding of the XQuery FLWOR expression to make a syntactically equivalent XPath query. Predicates of the LET binding may also be incorporated with the next steps, without altering the predicates.