Explaination

Hello,

can someone help me with the explaination of what the section of script below is doing?

sql 'alter system archive log current';
backup
format 'c:\temp\al_t%t_s%s_p%p'
archivelog all
delete input;

Thanks

Archive current log, Archive archived redo logs result goes in one file with unique name then delete archived redo logs.
Best wishes.

OK,

so if I then loose the redo logfile from the hard disk how do I recreate the file?

Thanks

run {
allocate channel ch1 type disk;
resore archivelog all;
}

This recovers the archievelog but what about the redo log files?

Thanks

It is the same,
'archivelog' = 'archived redo logs' it is almost the same as 'redo log'

I know but I have physically deleted one of the online redo logs to see how I recover from that and I get the following after restoreing the database :

SVRMGR> STARTUP;
ORACLE instance started.
Total System Global Area 73242652 bytes
Fixed Size 75804 bytes
Variable Size 20631552 bytes
Database Buffers 52428800 bytes
Redo Buffers 106496 bytes
Database mounted.
ORA-00313: open failed for members of log group 1 of thread 1
ORA-00312: online log 1 thread 1: 'F:\ORACLE\ORA817\DATABASE\LOGPICIS1A.ORA'

The LOGPICIS1A.ORA is the redo log.

You shoud not delete online redo logs. I told about archived redo logs.
You should delete info from the db about your log member and add new member to log group.

Ok what I am doing is creating different senarios and trying to recover from them, but this one is tricky. I had assumed that you could rebulid the redo logs somehow after said a hard disk failure. Is this not possible? What do you do if you loose the online redo logs?

It is possible rebuild online redo logs if you have lost them. Just recriate them. If I lose one online redo log from log group - I have another member on another HD, I hope 2 HD cant crush in the same time. So I just copy or rename log member.

I have 4 groups with one member in each. These 4 files are on the same hard disk. I deleted on of the files. Can I just rename one of the other files and use it or is the proces a little more compilcated.

Do you know the difference between GROUP and mebers of a GROUP? How can you replace one member from a group for another member in another group. The contents is TOTALLY different

So then how do I recreate this full group which is one file on the hard disk and one memeber?

Thanks

process is long you better check it for yourself

http://metalink.oracle.com/metalink/...p_id=1044466.6

http://metalink.oracle.com/metalink/...p_id=1060608.6

Diggers,

If you have deleted a redolog before it archived then you are knackered!!

You must open database with the 'resetlogs' option and hence will suffer data loss.


You should ALWAYS multiplex your redologs over seperate devices to guard against this.

Kind regards,