Database

Question

Why b/b+ tree used for DB index rather than AVL tree?

Comments

B/B+ has larger fan out. IMO

Answer 1

AVL Tree is balanced Binary Search Tree, in BST each node contains only one key so it will be a huge BST if we use it for indexing.
While in B/B++ tree a node contains many keys, the tree will have less height. Each node has the equal size to a Block size. In case of BST, I/O cost will be more because we have to fetch lots of data blocks.