META-DATA INDEXING FOR XPATH LOCATION STEPS

In accordance with a method of encoding meta-data associated with tree-structured data, a first set of elements of a plurality of elements in the tree-structured is associated explicitly with explicit meta-data levels, and a second set of elements of the plurality of elements is associated by inheritance with explicit meta-data levels of closest ancestor elements of the first set of elements. The plurality of elements is packed into a plurality of leaf nodes of an index structure. The plurality of leaf nodes is merged into a plurality of non-leaf nodes until a root non-leaf node is generated. The plurality of non-leaf nodes of the index structure is associated with indicators representing ranges of the explicit meta-data levels in the packed first set of elements, such that explicit meta-data level ranges of descendant non-leaf nodes are subsets of explicit meta-data level ranges of ancestor non-leaf nodes.