'Linear hashing' presentation slideshows

Advanced Data Structures NTUA Spring 2007 B+-trees and External memory Hashing

Advanced Data Structures NTUA Spring 2007 B+-trees and External memory Hashing. Model of Computation. Data stored on disk(s) Minimum transfer unit: a page(or block) = b bytes or B records N records -> N/B = n pages I/O complexity: in number of pages. CPU. Memory. Disk.

596 views • 47 slides

Database Systems ( ????? )

Database Systems ( ????? ). November 26/28, 2007 Lecture #9. Announcement. Hand in your assignment #4 on Wed. African Poverb. Every morning, a zebra wakes up, it knows that it must run faster than the fastest lion, or it will be eaten; every morning, a lion wakes up,

437 views • 43 slides

Outline: Hashing (5.9, 5.10, 3 rd . ed.; 13.8, 4 th , 5 th ed.; 17.8, 6 th ed.)

Outline: Hashing (5.9, 5.10, 3 rd . ed.; 13.8, 4 th , 5 th ed.; 17.8, 6 th ed.) external hashing static hashing & dynamic hashing hash function mathematical function that maps a key to a bucket address collisions collision resolution scheme open addressing chaining multiple hashing

503 views • 33 slides

Query Processing

Query Processing. General Overview. Relational model - SQL Formal & commercial query languages Functional Dependencies Normalization Physical Design Indexing Query Processing and Optimization. Review. Data Retrieval at the physical level:

494 views • 32 slides

Database Systems ( ????? )

Database Systems ( ????? ). November 28, 2005 Lecture #9. Announcement. Next week reading: Chapters 12 Pickup your midterm exams at the end of the class. Pickup your assignments #1~3 outside of the TA office 336/338. Assignment #4 & Practicum #2 are due in one week.

411 views • 28 slides

Hash-Based Indexes

295 views • 28 slides

CS 405G: Introduction to Database Systems

CS 405G: Introduction to Database Systems. 23 Hashing Chen Qian University of Kentucky. B+-tree Organization. Internal node. Leaf node. Review. B + -tree Insert Find correct leaf L. Put data entry onto L . If L has enough space, done !

393 views • 26 slides

CPSC 461 Final Review I

CPSC 461 Final Review I. Hessam Zakerzadeh Dina Said. 9.1) What is the most important difference between a disk and a tape?. 9.1) What is the most important difference between a disk and a tape?

516 views • 25 slides

Hash-based Indexes

Hash-based Indexes. CS 186, Spring 2006 Lecture 7 R &G Chapter 11. HASH, x. There is no definition for this word -- nobody knows what hash is. Ambrose Bierce, "The Devil's Dictionary", 1911. Introduction. As for any index, 3 alternatives for data entries k* :

356 views • 25 slides

Database Systems ( ????? )

Database Systems ( ????? ). November 8, 2004 Lecture #9 By Hao-hua Chu ( ??? ). Announcement. Midterm exam: November 20 (Sat): 2:30 PM in CSIE 101/103 Assignment #6 is available on the course homepage. It is due on 11/24 It is very difficult Suggest you do it before midterm exam

445 views • 24 slides

Hash-Based Indexes

Hash-Based Indexes. Chapter 11. Introduction. As for any index, 3 alternatives for data entries k*: Data record with key value k <k, rid of data record with search key valuek> <k, list of rids of data records with search key k> Choice orthogonal to the indexing technique

544 views • 23 slides

Hashing

Hashing. B+ Tree: The Most Widely Used Index. Insert/delete at log F N cost; keep tree height-balanced . (F = fanout, N = # leaf pages) Minimum 50% occupancy (except for root). Each node contains

309 views • 23 slides

External Memory Hashing

External Memory Hashing. Model of Computation. CPU. Memory. Data stored on disk(s) Minimum transfer unit: a page = b bytes or B records (or block) N records -> N/B = n pages I/O complexity: in number of pages. Disk. I/O complexity.

314 views • 22 slides

Hash-Based Indexes

Hash-Based Indexes. Chapter 11. Introduction. Hash-based indexes are best for equality selections . Cannot support range searches. A good hash function is: Random Uniform Static and dynamic hashing techniques exist; trade-offs similar to ISAM vs. B+ trees. Static Hashing.

353 views • 22 slides

Hashing

Hashing. Selection Queries. B+-tree is perfect, but.... to answer a selection query (ssn=10) needs to traverse a full path. In practice, 3-4 block accesses (depending on the height of the tree, buffering) Any better approach?.

224 views • 22 slides

Hash-Based Indexes

Hash-Based Indexes. Comments. Comments on the exam? $1 for anyone who solved the puzzle. Rope Puzzle?. Who checked out Bill Gates speech?. Introduction. As for any index, 3 alternatives for data entries k* : Data record with key value k

273 views • 21 slides

Instructor: Chen Li

CS 222P: Principles of Data Management Notes # 8 Static Hashing, Extendible Hashing ? Linear Hashing. Instructor: Chen Li. Introduction. Hash -based indexes are best for equality selections . Cannot support range searches.

511 views • 20 slides

Hash-Based Indexes

Hash-Based Indexes. Chapter 11. Introduction. As for any index, 3 alternatives for data entries k* : Data record with key value k < k , rid of data record with search key value k > < k , list of rids of data records with search key k > Choice orthogonal to the indexing technique

289 views • 19 slides

Hash-Based Indexes

Hash-Based Indexes. Chapter 11. Introduction. As for any index, 3 alternatives for data entries k* : Data record with key value k < k , rid of data record with search key value k > < k , list of rids of data records with search key k > Choice orthogonal to the indexing technique

262 views • 19 slides

Tree-based Indexing

Tree-based Indexing. Hessam Zakerzadeh. ISAM ( Indexed Sequential Access Method ). ISAM was originally developed by IBM for mainframe computers Allows records to be accessed: sequentially (in the order they were entered) randomly (with an index). ISAM ( Indexed Sequential Access Method ).

404 views • 15 slides