The article explains how to use the Dbvisit Standby database for reporting purposes during certain time frames in a day. This is solution is for customers who are not worries about the data being latest or in sync with primary and are ok with using old data.
With Dbvisit Standby, as with any physical Oracle standby database solution, the standby database can either be in:
- Apply mode
- Where changes from the primary are applied to bring it up to date.
- Read-only mode
- Where the database is open for query access but at which time the changes from production are not applied.
Using Dbvisit Standby makes it possible to easily automate a schedule to switch between these different modes. For example, the following could be set up:
- Apply mode: Apply queued up changes from production.
- 8am - 12pm
- Read only mode: Have the standby database open for querying by your team. Bear in mind that by midday it will now be up to four hours behind production. For many customers this is acceptable.
- Apply mode: Apply changes from the primary database to bring it up to date with that instance.
- Read only mode: Have the standby database open for querying again.
Two further comments on this:
- Changes from production are actually delivered to the DR server the entire time, so in a sense if they have been successfully transferred then you are protected in terms of DR.
- You only need have the Standby database in apply mode for as long as needed to apply the queued up changes from production before you open it back up for read only access. The actual time required for this depends on the volume of redo generated and the speed of the components (ie: servers) in your system.
Mike Donovan November 20, 2012 08:25