A method and system are provided for navigation of a data structure. The method includes receiving an input path expression (104) for a query of a data structure (101) to locate one or more elements (110) in the data structure (101) at runtime. The input path expression (104) includes one or more path steps. The method includes accessing a schema (103) of the data structure (101) and obtaining information relating to the one or more elements (110). The path expression (104) is modified to specify an index in one or more of the path steps to limit the number of occurrences of an element located in a path step. In one embodiment, modifying the path expression (104) also expands any wildcard characters and specifies one or more full paths of the elements (110), wherein if there are two or more full paths they are combined by a union operator, and the modified path expression is used to query (111) the data structure (101) at runtime.