Re: C-ISAM logfiles and recovery time

>From: uunet!perfmap.austin.ibm.com!bj (Bjarne Hansen) >Subject: C-ISAM logfiles and recovery time >Date: Wed, 19 May 1993 00:23:01 GMT >X-Informix-List-Id: <news.3373> >We are using C-ISAM with logfiles, isbegin() and iscommit(). >This works great, but we are concerned about recovery time in >case of a system failure. According to the docs, a failure will >require us to restore the latest backup, and do isrecover() >from the logfiles. Is this correct ? Yes, this is correct. >Can C-ISAM not recover the corrupted datafiles from the logfiles ? Yes, it uses the log file to replay the transactions since the last known point where the files were consistent -- which is the state as of the last backup. All recovery systems need a reference point from which to start the recovery. Alternatively, you can consider using audit trails instead of transaction logs. An audit trail logs the changes to a single file. It is not as comprehensive as a transaction log (because, for example, if there are changes made to two tables, one audited and the other unaudited, then the changes to the unaudited table will be lost without a transaction log). >Another question/wish: Is there a way to make C-ISAM use Online tables ? No. Yours, Jonathan Leffler (johnl@obelix.informix.com) #include <disclaimer.h>