A breadth-first join module receives, at a runtime, a query for travel data, wherein the travel data is stored in a data store, the data store comprising parent and child data structures arranged in a hierarchy. The breadth-first join module identifies a first child data structure associated with the travel data, the first child data structure comprising a plurality of pointers, wherein each of the plurality of pointers is associated with one of a plurality of first level parent data structures in the data store and queries each of the plurality of first level parent data structures to resolve the plurality of pointers in the first child data structure, wherein the plurality of first level parent data structures comprise travel data objects associated with the plurality of pointers, and wherein at least one of the plurality of first level parent data structures comprises a pointer to a second level parent data structure. The breadth-first join module queries the second level parent data structure to resolve the pointer in the at least one first level parent data structure, wherein all of the plurality of pointers in the first child data structure are resolved prior to querying the second level parent data structure.