Does Oracle overwrite rollback information for uncommitted transactions?

Home
Topics
Oracle database administration
Oracle database backup and recovery
Does Oracle overwrite rollback information for uncommitted transactions?

Does Oracle overwrite rollback information for uncommitted transactions?

Brian Peasland, Database Administrator, SGT, Inc.

If in Oracle 9i or 10g the undo_retention parameter is set to 900 sec and after that period if unexpired (uncommitted) data is overwritten by other transactions in some undo segment, then how does rollback work in that case? As undo has been overwritten which was supposed to be used for rollback?

Requires Free Membership to View

Login

By submitting your registration information to SearchOracle.com you agree to receive email communications from TechTarget and TechTarget partners. We encourage you to read our Privacy Policy which contains important disclosures about how we collect and use your registration and other information. If you reside outside of the United States, by submitting this registration information you consent to having your personal data transferred to and processed in the United States. Your use of SearchOracle.com is governed by our Terms of Use. You may contact us at webmaster@TechTarget.com.

Oracle will not overwrite the rollback information for uncommitted transactions, even if the UNDO_RETENTION time has passed. Oracle will overwrite this information only for committed transactions. So if a transaction runs for longer than 900 seconds in your example, you will still be able to rollback that transaction.

Dig Deeper

People who read this also read...

Show me more

This was first published in June 2007

Join the conversationComment

Share

Comments

Results

Contribute to the conversation

All fields are required. Comments will appear at the bottom of the article.

Back to top

More from Related TechTarget Sites

Data Management
Business Analytics
SAP
SQL Server
Java
Data Center
Content Management
Financial Applications

Data Management
- Bank of America IT exec: EIM drivers key to shaping project plans
  
  The most effective programs are shaped by clearly stated business objectives, according to a senior information architect at Bank of America.
- In-memory database caching helps AltEgo bring online avatars to life
  
  In-memory database caching technology is helping gamers take charge of their online identities.
- Datachick gives 'big data' a verbal beat down at Enterprise Data World
  
  "Big data" technologies took a verbal shellacking from consultant and well-known Twitterer Karen Lopez in an Enterprise Data World conference session.
Business Analytics
- On the go the way to go? Answer lies with building mobile BI business case
  
  According to a recent Gartner survey, mobile technology is the second most important priority for CIOs in 2012, but building the business case is easier said than done.
- Basic vs. complex: Companies walk the line on analytics best practices
  
  Businesses looking to build effective business intelligence and analytics programs have to toe the line between focusing on the basics and using new technology to build more complex BI systems.
- Real estate company refines, expands geographic information system
  
  Marcus & Millichap shakes off its archaic data cleansing and analytics system for more automated processes, enabling the firm to explore its data on a more granular level.
SAP
- Spinnaker to fight Rimini Street for third-party SAP support market
  
  It was only a matter of time before SAP third-party support and maintenance provider Rimini Street had some competition from other vendors. That time has come.
- SAP SapphireNow attendees heading to Orlando looking for answers
  
  SapphireNow attendees are looking for answers to a long list of questions on issues ranging from mobility to the acquisition of SuccessFactors and SAP’s long-term cloud strategy.
- Eight stories tell the tale of SAP mobility
  
  From its growing ecosystem to Sybase Afaria, here is a collection of SearchSAP.com stories that clarify what SAP’s evolving mobile roadmap means for customers.
SQL Server
- Configuring SSRS the easy way
  
  Demystify the SQL Server Reporting Services (SSRS) configuration process. Get an overview of this tool and guidelines for how to set up each screen in SSRS from industry professional Roman Rehak.
- SQL Server Upgrade Advisor, Upgrade Assistant can ease transition pains
  
  You probably think you’re ready to upgrade to the new release, but you might not be as prepared as you think. Before you upgrade, there are some tools to become familiar with, says Bob Sheldon.
- ODBC drivers replacing OLE DB? Say what?
  
  After years of telling SQL Server users to avoid ODBC in favor of OLE DB, Microsoft has suddenly reversed its position and advised going back to ODBC. Why? And what should you do about it?
Java
- Scaling up and scaling out to meet new business demands
  
  Scaling up and scaling out are two ways for growing businesses to increase productivity, but doing so blindly may be more costly than it's worth.
- On-demand computing models support Web application scalability
  
  The on-demand nature of cloud computing has put scalable Web applications within easy reach for businesses of all sizes.
- Automate Web server load balancing for high scalability
  
  Automating Web server load balancing tasks provides high scalability for enterprise applications.
Data Center
- Why Zynga moved from public cloud to hybrid cloud
  
  The subtext of Zynga’s “hybrid cloud” strategy is that at a certain scale, public cloud ain’t cheap.
- Dell microserver gives energy-efficient IT shops a glimpse of Ivy Bridge
  
  New Dell microservers include power-efficient Ivy Bridge processors based on Intel’s 22-nm manufacturing process.
- How to balance three-phase power to maximize UPS capacity
  
  Apply these techniques to balance the three-phase power load and avoid unnecessarily buying a costly new UPS.
Content Management
- Document management system success relies on proper scope
  
  Document management system success relies on proper planning for the scope and needs of your organization -- not only today, but in the future, says consultant Steve Weissman.
- Well-planted SharePoint 2010 backup strategy could help save the farm
  
  A SharePoint farm backup as part of an enterprise SharePoint 2010 backup strategy is simple, but on its own might not be enough. Brien M. Posey points out the other important considerations.
- Picking the right CMS tool may require IT, marketing unity
  
  The key to choosing the ideal content management system is getting the IT and marketing departments to work together as a team, experts say.
Financial Applications
- Basic planning, data cleansing seen as crucial to HR system integration
  
  Save time and money by establishing human resources processes and scrubbing data before embarking on a project to integrate systems, industry watchers say.
- SaaS HCM growing, but some prefer customization of on-premises HCM
  
  As more companies consider taking human capital management to the cloud, analysts say the on-site version also has its benefits.
- From Excel to financial analytics software: Users, experts share tips
  
  When preparing for the transition, companies should review existing processes, involve end users and clean up the data.

All Rights Reserved, Copyright 2003 - 2012, TechTarget