Software → Databases
B-Tree
A balanced tree data structure commonly used for database and filesystem indexes.
Motivation
A B-Tree solves the problem of indexing large datasets on disk while minimizing slow disk reads.
Where it fits
It belongs to databases and data structures and is a common foundation for relational database indexes.
Mental model
A B-Tree is a wide, balanced search tree. Each node stores many keys so fewer disk pages are needed during lookup.
Important details
B-Trees are optimized for block storage. They support range queries well and keep data sorted.
Common mistakes
- Thinking B-Trees are just binary search trees.
- Ignoring the disk/page motivation behind their shape.