How can you get the tree-like view of commits in terminal? git log –graph –oneline –all is a good start. You may get some strange letters. They are ASCII codes for colors and structure. To solve this problem add the following to your .bashrc: export LESS=”-R” such that you do not need use Tig’s ASCII … Read more
Here: public class Tree<T> { private Node<T> root; public Tree(T rootData) { root = new Node<T>(); root.data = rootData; root.children = new ArrayList<Node<T>>(); } public static class Node<T> { private T data; private Node<T> parent; private List<Node<T>> children; } } That is a basic tree structure that can be used for String or any other … Read more
Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax. WITH RECURSIVE MyTree AS ( SELECT * FROM MyTable WHERE ParentId IS NULL UNION ALL SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id ) SELECT * FROM MyTree; … Read more
My favorite answer is as what the first sentence in this thread suggested. Use an Adjacency List to maintain the hierarchy and use Nested Sets to query the hierarchy. The problem up until now has been that the coversion method from an Adjacecy List to Nested Sets has been frightfully slow because most people use … Read more