CS2007Ch14

... Used to locate items in an external data file Contains an index record for each record in the data file ...

... Used to locate items in an external data file Contains an index record for each record in the data file ...

B Tree Index Files by Huy Nguyen

... • Binary tree only have 2 children max. • For large files binary tree will be too high because of the limit of children and not enough keys per records. • Btrees disk size can have many children depending on the disk block. • Btrees are more realistic for indexing files because they easily maintain ...

... • Binary tree only have 2 children max. • For large files binary tree will be too high because of the limit of children and not enough keys per records. • Btrees disk size can have many children depending on the disk block. • Btrees are more realistic for indexing files because they easily maintain ...

Concurrent R

... An R-tree is a depth balanced tree with a dynamic index structure ◦ Leaf nodes point to actual keys ◦ The number of entries in a node is between m and N (1 < m ≤ N) ◦ Root might have between 1 and N entries. ◦ All leaf nodes are at the same level ◦ The key for each internal node is the minimum bound ...

... An R-tree is a depth balanced tree with a dynamic index structure ◦ Leaf nodes point to actual keys ◦ The number of entries in a node is between m and N (1 < m ≤ N) ◦ Root might have between 1 and N entries. ◦ All leaf nodes are at the same level ◦ The key for each internal node is the minimum bound ...

What is a B

... m non-null references to data blocks B0, B1, B2, . . . , Bm-1. The number of keys is one less than the number of non-null references. 4. The keys in a non-leaf node and the referenced blocks are ordered as: B0, p1, B1, p2, B2, . . . , pm-1, Bm-1 such that: • All data in block B0 correspond to keys t ...

... m non-null references to data blocks B0, B1, B2, . . . , Bm-1. The number of keys is one less than the number of non-null references. 4. The keys in a non-leaf node and the referenced blocks are ordered as: B0, p1, B1, p2, B2, . . . , pm-1, Bm-1 such that: • All data in block B0 correspond to keys t ...

CS2351 Data Structures

... Ans. Yes. We must read all #s to find max, which needs at least N/B I/Os ...

... Ans. Yes. We must read all #s to find max, which needs at least N/B I/Os ...

Notes

... days main memory is almost as slow relative to the processor as disk drives were to main memory when B-trees were first introduced! ...

... days main memory is almost as slow relative to the processor as disk drives were to main memory when B-trees were first introduced! ...

B-Trees

... Finally, what if neither sibling is more than half full? Then, 3. the page and either sibling are concatenated or coalesce, absorbing the parent key. Concatenation is the opposite of splitting. It removes a key from the parent page, so one of (1), (2) or, recursively, (3) is needed to ensure the res ...

... Finally, what if neither sibling is more than half full? Then, 3. the page and either sibling are concatenated or coalesce, absorbing the parent key. Concatenation is the opposite of splitting. It removes a key from the parent page, so one of (1), (2) or, recursively, (3) is needed to ensure the res ...

Part 2 - B-Tree

... C Similar to indexed sequential files, B-trees can be accessed both sequentially and directly. ...

... C Similar to indexed sequential files, B-trees can be accessed both sequentially and directly. ...

Chapter 10

... If the desired element is less than the current node, try the left child next If the desired element is greater than the current node, try the right child next To insert an element, perform a search to find the proper spot ...

... If the desired element is less than the current node, try the left child next If the desired element is greater than the current node, try the right child next To insert an element, perform a search to find the proper spot ...

CSE 114 – Computer Science I Lecture 1

... new, smaller tree (can be called a subtree) – A binary tree has a left subtree & right subtree • Depth of a node – starting at a node, the number of steps up to reach the root • Depth of a tree – the maximum depth of any of its leaves ...

... new, smaller tree (can be called a subtree) – A binary tree has a left subtree & right subtree • Depth of a node – starting at a node, the number of steps up to reach the root • Depth of a tree – the maximum depth of any of its leaves ...

Binary Search Trees

... – If the tree is a linear chain of n nodes, however, the same operations take (n) worst-case time. ...

... – If the tree is a linear chain of n nodes, however, the same operations take (n) worst-case time. ...

7 Data Structures – Binary Search Trees

... – If the tree is a linear chain of n nodes, however, the same operations take (n) worst-case time. ...

... – If the tree is a linear chain of n nodes, however, the same operations take (n) worst-case time. ...

1 Balanced Binary Search Trees

... A binary search tree is a binary tree with values at the nodes arranged such that the values at the nodes in the right subtree of a node is at least the value of the node and the values at nodes in the left subtree of the node is at most the value of the node. It supports three operations:(Insert, D ...

... A binary search tree is a binary tree with values at the nodes arranged such that the values at the nodes in the right subtree of a node is at least the value of the node and the values at nodes in the left subtree of the node is at most the value of the node. It supports three operations:(Insert, D ...

In computer science, a B-tree is a tree data structure that keeps data sorted and allows searches, sequential access, insertions, and deletions in logarithmic time. The B-tree is a generalization of a binary search tree in that a node can have more than two children (Comer 1979, p. 123). Unlike self-balancing binary search trees, the B-tree is optimized for systems that read and write large blocks of data. B-trees are a good example of a data structure for external memory. It is commonly used in databases and filesystems.