This link has been bookmarked by 12 people . It was first bookmarked on 18 Sep 2006, by morrita.
-
30 Oct 09
-
In computer science, a B-tree is a tree data structure that keeps data sorted and allows searches, insertions, deletions, and sequential access in logarithmic amortized time. The B-tree is a generalization of a binary search tree in that more than two paths diverge from a single node.[1]
-
-
15 Sep 09
-
a B-tree is a tree data structure that keeps data sorted and allows searches, insertions, deletions, and sequential access in logarithmic amortized time.
-
The B-tree is a generalization of a binary search tree in that more than two paths diverge from a single node[1]
- 19 more annotations...
-
-
the B-tree is optimized for systems that read and write large blocks of data.
-
In order to maintain the pre-defined range, internal nodes may be joined or split.
-
Each split node has the required minimum number of keys.
-
A B-tree is kept balanced by requiring that all leaf nodes are at the same depth.
-
B-trees have substantial advantages over alternative implementations when node access times far exceed access times within nodes.
-
practical B-trees using secondary storage want a large number of child nodes to improve performance.
-
In the narrow sense, a B-tree stores keys in its internal nodes but need not store those keys in the records at the leaves.
-
-
Usually, sorting and searching algorithms have been characterized by the number of comparison operations that must be performed using order notation.
-
The time to read a record on a disk drive can dominate the time needed to compare keys once the record is available.
-
Inserting a record before the first record in the file requires shifting all of the records down one.
-
- Every node has at most m children.
- Every node (except root and leaves) has at least m⁄2 children.
- The root has at least two children if it is not a leaf node.
- All leaves appear in the same level, and carry information.
- A non-leaf node with k children contains k–1 keys.
A B-tree of order m (the maximum number of children for each node) is a tree which satisfies the following properties:
-
This relationship between U and L implies that two half-full nodes can be joined to make a legal node, and one full node can be split into two legal nodes
-
A B-tree of depth n+1 can hold about U times as many items as a B-tree of depth n,
-
Insert the separation value in the node's parent
-
If the splitting goes all the way up to the root, it creates a new root with a single separator value and two children
-
the most efficient way to construct the initial B-tree is not to insert every element in the initial collection successively, but instead to construct the initial set of leaf nodes directly from the input, then build the internal nodes from these.
-
The B-tree is also used in filesystems to allow quick random access to an arbitrary block in a particular file.
-
-
-
29 Jun 09
-
-
In computer science, a B-tree is a tree data structure that keeps data sorted and allows searches, insertions, and deletions in logarithmic amortized time. Unlike self-balancing binary search trees, it is optimized for systems that read and write large blocks of data. It is most commonly used in databases and filesystems.
-
-
-
In computer science, a B-tree is a tree data structure that keeps data sorted and allows searches, insertions, and deletions in logarithmic amortized time. Unlike self-balancing binary search trees, it is optimized for systems that read and write large blocks of data. It is most commonly used in databases and filesystems.
-
-
04 May 09
-
03 Nov 08
-
07 Apr 07
-
2-3 B-trees might be useful in main memory
-
-
18 Sep 06
-
06 Dec 04
Would you like to comment?
Join Diigo for a free account, or sign in if you are already a member.