A method may include generating, based on a representation of a hierarchy stored in a database, a visiting sequence data structure. The hierarchy may be stored in a table in the database. Each of a plurality of rows comprising the table may correspond to one of a plurality of nodes comprising the hierarchy. The visiting sequence data structure may include a row vector specifying an order for traversing the plurality of nodes in the hierarchy. A hierarchical window function may be executed by iterating through the plurality of rows in the table in accordance with the order specified by the row vector. The execution of the hierarchical window function may further include determining, for a first node in the hierarchy, a summary value corresponding to a first value of the first node and a second value of a second node descendent from the first node.