[ http://issues.apache.org/jira/browse/DERBY-239?page=comments#action_12356240 ]
Suresh Thalamati commented on DERBY-239: ---------------------------------------- What to do if backup is started in a transaction that already has unlogged operations executed? In previous discussions about online backup, it was concluded that existing backup procedures calls will WAIT for the transaction with unlogged operations to commit before proceeding with the backup. One issue that was missing from the discussion was, what to do if user starts a backup in the same transaction that has unlogged operations executed before the backup call. WAIT will not be an acceptable option here, because backup call will wait forever. I can think of two ways this issue can be addressed: 1) Add a restriction that backup procedures can only be called in a brand NEW transaction. And also implicitly commit the backup transaction at the end of the backup. Commit is not required as such to solve this problem, but it would be cleaner because backup itself is not a rollback-able operation. 2) Make backup procedures fail, if transaction that it is started in contains unlogged operations. I am inclined towards implementing the first option. Any comments/suggestion will be appreciated. Thanks -suresht > Need a online backup feature that does not block update operations when > online backup is in progress. > -------------------------------------------------------------------------------------------------------- > > Key: DERBY-239 > URL: http://issues.apache.org/jira/browse/DERBY-239 > Project: Derby > Type: New Feature > Components: Store > Versions: 10.1.1.0 > Reporter: Suresh Thalamati > Assignee: Suresh Thalamati > Attachments: onlinebackup.html, onlinebackup_1.diff > > Currently Derby allows users to perfoms online backups using > SYSCS_UTIL.SYSCS_BACKUP_DATABASE() procedure, but while the backup is in > progress, update operations are temporarily blocked, but read operations can > still proceed. > Blocking update operations can be real issue specifically in client server > environments, because user requests will be blocked for a long time if a > backup is in the progress on the server. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
