Re: HELP: Long (lasting) transactions?

paul sellars (paul@boothbc.demon.co.uk) wrote: ( referring to the way Informix OnLine is implemented:) : The log file containing the start of transaction (and following log files) : cannot be archived until the transaction has ended. If, after the start This is not true. It can be archived. It cannot be reused, however, so the conclusions drawn remain true. : but before the end of the long transaction, enough other transactions : occur to fill the remaining logs then the long transaction would be rolled : back. : Also, any rows you update, insert, or delete within the transaction : will remain locked until the end of transaction. This basically means that with OnLine, you would need to dedicate enough disk to transaction logs to last for the duration of the longest transaction plus a safety margin. This may or may not be feasible and/or palatable. If you are generating Gbs of log per day then it is unlikely to be acceptable, if you only generate a few kb per day then it is not likely to be a problem. I have seen OnLine sites set up such that it took circa 1 week to cycle through the transaction logs. : I would be interested to know how Oracle would handle this. If Oracle : starts a long transaction in a log file then fills all remaining log files : what do you do? If you archive the logs how do you rollback the transaction? : How does it handle locking during these transactions? : It might be an idea to go back to the people who told you Oracle would : be ok and get confirmation. : -- : -------------------------------------------------------------------------- : paul sellars,humberside,u.k. : ========================================================================== -- graeme -- Disclaimer: The author's opinions are his own, and not necessarily those of Pyramid Technology Ltd. or Pyramid Technology Inc. --------------------------------------------------------------------------- -m------- Graeme Sargent Voice: +44 (0)252 373035 ---mmm----- Senior Database Consultant Fax : +44 (0)252 373135 -----mmmmm--- Pyramid Technology Ltd. Telex: Tell who??? -------mmmmmmm- Farnborough, Hants GU14 7PL Email: graeme@pyra.co.uk --------------------------------------------------------------------------- We have the technology. The tricky bit is learning how to use it.