Call (800) 766-1884 for Oracle support & training
Free Oracle Tips


Oracle Consulting Support
Oracle Upgrades
Use New Oracle Features
Oracle Replication Support
Oracle Training
Remote Oracle DBA
System Documentation
Oracle Tips
Oracle Performance
 

Free Oracle Tips


 

HTML Text

BC Oracle tuning

Oracle training

Oracle support

Remote Oracle

 

 

   
  Oracle Tips by Burleson

True story

A user wanted to change a rate for one department.  He created and ran his update statement, but he did not use a WHERE clause to limit the changes to the one department.  All rows where changed.  He realized his mistake, knowing that he did not want to commit the incorrect changes; he instead logged off to go get the DBA to help him.  His log off committed the bad data and the company had to restore the previous night’s backup and recover the database forward to a time before the user made his changes. 

A rollback is issued whenever a user issues the rollback command, abnormally exits the database or the database crashes. 

Once a commit has been issued, all changes are permanent.  The previous state of the data is permanently lost.  Other users will see the committed changes.   

Once a rollback has been issued, the changes are undone back to the last commit, rollback or log on.  All of the changes are lost (no roll forward). 

 


The above book excerpt is from:

Easy Oracle SQL

Get Started Fast writing SQL Reports with SQL*Plus

ISBN 0-9727513-7-8

Col. John Garmany 

http://www.rampant-books.com/book_2005_1_easy_sql.htm

  
 

Oracle performance tuning software 
 
 
 
 

Oracle performance tuning book

 

 
 
 
Oracle performance Tuning 10g reference poster
 
 
 
Oracle training in Linux commands
 
Oracle training Excel
 
Oracle training & performance tuning books
 

 

   

Copyright © 1996 -  2014 by Burleson. All rights reserved.

Oracle® is the registered trademark of Oracle Corporation.