3. The computer-readable storage medium of claim 1 wherein the operations further comprise, based on the analyzing, creating a tree in which a first term in a given grouping of the groupings is defined as a parent node in the tree and a second term in the given grouping is defined as a child node of the parent node in the tree, both the first term and the second term in the given grouping being consecutive text-based terms present in the order collection.
3. The computer-readable storage medium of claim 1 wherein the operations further comprise, based on the analyzing, creating a tree in which a first term in a given grouping of the groupings is defined as a parent node in the tree and a second term in the given grouping is defined as a child node of the parent node in the tree, both the first term and the second term in the given grouping being consecutive text-based terms present in the order collection. 7. The computer-readable storage medium of claim 3 wherein the operations further comprise: maintaining positional information for each parent node in the tree, the positional information providing a mapping to a location in the ordered collection where a corresponding parent text-based term is located; and maintaining positional information for each child node in the tree, the positional information providing a mapping to a location in the ordered collection where a corresponding child text-based term is located.