There is no RDBMS that will choke on a table with every animal in existence in it. To my knowledge, the two most common ways of handling this: self-referential

There is no RDBMS that will choke on a table with every animal in existence in it. To my knowledge, the two most common ways of handling this: self-referential nested set[1] and with a join table[2] 1. https://en.wikipedia.org/wiki/Nested_set_model https://en.wikipedia.org/wiki/Nested_set_model 2. https://coderwall.com/p/lixing/closure-tables-for-browsing-trees-in-sql https://coderwall.com/p/lixing/closure-tables-for-browsing-t...