What do you mean by "You will be unprotected"?
I am very clear with the concepts that you explained in this expert response, "Taking export backup of standby database
," but I only wish to understand what exactly you are trying to say by "you will be unprotected," the very last sentence, as below. Your feedback will be helpful to me. Thanks.
QUESTION POSED ON: 31 July 2006
Is it possible to take an export backup of a standby database? And how?
What mode is the standby database running in? If the standby database is in managed recovery mode, then you cannot connect to the database and read the table's contents, therefore you will not be able to take an export of the standby database. However, you can switch the standby database to READ ONLY mode and create your export dump. During this time, your standby database will not be applying any redo and it will become out of sync with your production database. You can have the standby catch up with production once you place it back in managed recovery mode. But during this time, you will be unprotected.
I must admit that my last sentence was probably not written correctly. What I meant to say was that while you have the standby database in READ ONLY mode, you do not have a standby to use in the event that your production database terminates. And isn't this the reason you set up a standby database in the first place? Should a problem occur with your production instance, you will have to stop your export and have your standby database play catch-up, applying all changes to production that had occurred since you placed the standby database in READ ONLY mode. At this time, you can switch the standby to the primary role. If this were my company, this lag time would be unacceptable. The standby database is there to quickly get the database up and running again should the production database or its server have a catastrophic failure.
This was first published in February 2007