B-tree

B-tree

[′bē ‚trē]

(computer science)

balanced-tree

B-tree

(algorithm)

A multi-way balanced tree.

The "B" in B-tree has never been officially defined. It could stand for "balanced" or "Bayer", after one of the original designers of the algorithms and structure. A B-tree is _not_ (necessarily?) a "binary tree".

A B+-tree (as used by IBM's VSAM) is a B-tree where the leaves are also linked sequentially, thus allowing both fast random access and sequential access to data.

[Knuth's Art of Computer Programming].

B-tree

(Balanced-tree) A technique for organizing indexes. In order to keep access time to a minimum, B-tree stores the data keys in a balanced hierarchy that continually realigns itself as items are inserted and deleted. Thus, all nodes always have a similar number of keys.

B+tree is a version of B-tree that maintains a hierarchy of indexes while also linking the data sequentially, providing fast direct access and fast sequential access. The IBM mainframe VSAM access method uses the B-tree method. See Btrfs and VSAM.