Evaluation of multiple Xpath queries in a streaming XPath processor

摘要

Progressive evaluation of predicate expressions in streaming XPath processor. A method for evaluating multiple XPath predicate expressions of multiple XPath queries includes identifying includes determining hit of a location path in a SAX event. All XPath predicate expressions of all XPath queries corresponding to the location path are then identified. All leaf nodes in the XPath predicate expressions corresponding to the location path are then determined. Thereafter, storage of nearest parent nodes of the leaf nodes is checked. Each nearest parent node is a first parent node which is encountered while moving from a leaf node towards a root node in an XPath predicate expression and which requires storage for storing intermediate Boolean result. Results of parent nodes of the leaf nodes are the determined based on the checking. Thereafter, the results of the parent nodes are stored if the results of the parent nodes are Boolean results. Further, results of root nodes of the XPath predicate expressions are determined by progressively evaluating subsequent parent nodes of the parent node.