tailieunhanh - Oracle® Database Administrator's Guide

Automatic Locking Oracle locking is performed automatically and requires no user action. Implicit locking occurs for SQL statements as necessary, depending on the action requested. Oracle’s lock manager automatically locks table data at the row level. By locking table data at the row level, contention for the same data is minimized. Oracle’s lock manager maintains several different types of row locks, depending on what type of operation established the lock. The two general types of locks are exclusive locks and share locks. Only one exclusive lock can be placed on a resource (such as a row or a table);. | ORACLE Oracle Database Administrator s Guide 10g Release 2 B14231-02 May 2006 Oracle Database Administrator s Guide 10g Release 2 B14231-02 Copyright 2001 2006 Oracle. All rights reserved. Primary Author Steve Fogel Contributing Author Paul Lane Contributors David Austin Prasad Bagal Cathy Baird Mark Bauer Eric Belden Bill Bridge Allen Brumm Sudip Datta Mark Dilman Jacco Draaijer Harvey Eneman Amit Ganesh Vira Goorah Carolyn Gray Joan Gregoire Daniela Hansell Lilian Hobbs Wei Huang Robert Jenkins Bhushan Khaladkar Balaji Krishnan Vasudha Krishnaswamy Sushil Kumar Bill Lee Sue K. Lee Yunrui Li Ilya Listvinsky Bryn Llewellyn Rich Long Catherine Luu Scott Lynn Raghu Mani Colin McGregor Mughees Minhas Valarie Moore Niloy Mukherjee Sujatha Muthulingam Gary Ngai Waleed Ojeil Rod Payne Hanlin Qian Ananth Raghavan Ravi Ramkissoon Ann Rhee Tom Sepez Vikram Shukla Bipul Sinha Wayne Smith Jags Srinivasan Deborah Steiner Janet Stern Michael Stewart Mahesh Subramaniam Anh-Tuan Tran Alex Tsukerman Kothanda Umamageswaran Eric Voss Daniel M. Wong Wanli Yang Wei Zhang The Programs which include both the software and documentation contain proprietary information they are provided under a license agreement containing restrictions on use and disclosure and are also protected by copyright patent and other intellectual and industrial property laws. Reverse engineering disassembly or decompilation of the Programs except to the extent required to obtain interoperability with other independently created software or as specified by law is prohibited. The information contained in this document is subject to change without notice. If you find any problems in the documentation please report them to us in writing. This document is not warranted to be error-free. Except as may be expressly permitted in your license agreement for these Programs no part of these Programs may be reproduced or transmitted in any form or by any means electronic or mechanical for any purpose. If the Programs