1. A computer-implemented method executed by one or more processors, the method comprising: identifying a first object hierarchy including one or more objects, each of the one or more objects representing a query associated with a data set; identifying a second object hierarchy including one or more objects; and generating a merged object hierarchy including the one or more objects from the first object hierarchy and the one or more objects from second object hierarchy, the merged hierarchy combining objects from the first and second object hierarchies that match and share a common parent object, and separately maintaining objects from the first and second object hierarchies that match and do not share a common parent object.