Hierarchy v.s Relational

Which one is the best? All and None. You manage your needs. For a mom-pop store ( food/restaurants) can very effectively be managed with a spread-sheet or Access VBAs; You don't need to use heavy duties like SQL, Oracle etc. In the relational database, a huge  tables can be broken-down into smaller tables,  with some kind of coding handles called "keys", and you use these keys to manage individual tables without corrupting or   duplicating data. 

Modern DB's used by the all commercial giants.
Generalized Access Method (GUAM), it is a prism arrangement with a top level access options. Each level the access will split into this and that option. A pointer will access to the right page. What I am afraid of, data duplication, redundancy and you need a middle ware to handle it. (Link to the Business cases). One point this Hierarchical system used in 1969,by North American Rockwell company, to manage a project that sent the mankind to the moon 
File System: Hierarchies

Data Base :