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When a Standby database is open Read-only for queries, sorting, and reporting.
Requires a License.
The Standby still applies redo.
Also see - 9.2 Opening a Physical Standby Database - in
Oracle® Data Guard Concepts and Administration 11g Release 2 (11.2) E10700-02
Edited by: mseberg on Jan 29, 2013 8:03 AM
1 person found this helpful
Oracle Database 126.96.36.199 EE on Solaris 5.10If you OPEN database from MOUNT status. But you should have license to use feature of ADG(Active Data Guard)
I've read several threads here and poured through the documentation but this point still escapes me.
When does Data Guard turn into Active Data Guard?
Is it when the Standby is OPEN and in READONLY mode while redo logs are being actively applied?Yes, It can perform both tasks 1) Recovery 2) Read-Only Options
If I stop log apply and OPEN the Standby for READONLY access, is that just regular Data Guard?No, Your standby will not synchronized with primary. It is just readonly and LAG with primary.
I obviously want to use Data Guard but not pay for Active Data Guard at this point.Then put in MOUNT status and you cannot run any SELECT(Read-only) queries. :)
Where is this documented?You can refer features of Active Data Guard http://www.oracle.com/technetwork/database/features/availability/ds-activedataguard-11gr2-130305.pdf
Michael, if you're listening, this is right up your alley! :-)Yes, he is listening ;)
I didn't checked Mseberg comments, There is 1 minute of lag between Me and Mseberg :P
Edited by: CKPT on Jan 29, 2013 7:32 PM
Thanks very much guys!
I wish there was a way to assign 2 'CORRECT' answers. I had to give this one to Michael only because he slipped in there first but obviously both of you nailed it.
I'll go back and check the document references.
Just to clarify, if I stop log apply ( I know there will be a lag now from Primary ) and OPEN the Standby in READONLY mode, does that invoke the Active Data Guard license?
If I wanted to create say a 1 hour window where people could run queries against the Standby and then restart the log apply later (back in MOUNT mode) to re-sync with the Primary, is there a way to do that without invoking Active Data Guard?
You guys rock!!
Hello,1 person found this helpful
When the standby database is opened in read only mode and is not under recovery stage, then it isn't an active dataguard.
You can have it opened in read only mode and allow users to access the standby database. But, recovery would be not be taking place.
Hello;1 person found this helpful
My opinion is no since Data Guard would not be "Active" I believe Its OK. But only Oracle's answer really counts.
OPEN the Standby in READONLY mode, does that invoke the Active Data Guard license?
I don't have a document to support this answer. But this may help :
Re: Active Data Guard License is technical or legal ?
The other option is Logical Standby. This would allow what you want without License costs. The downside is you lose an exact copy of your Primary or have to cascade from the physical standby.
Edited by: mseberg on Jan 29, 2013 8:48 AM
Edited by: mseberg on Jan 29, 2013 9:00 AM
Thanks Shivananda and Michael
I think I've got a handle on it now.
Maybe the docs aren't very explicit so people accidentally start using the ADG features and end up paying for the option. But, Oracle wouldn't do that, would they?? :-)
Thanks again for all your help.
If you are even considering Active DG then do yourself a favor and check out Shareplex for Oracle. Better product, more flexibility to do more things ADG cannot do at a more consumer friendly cost.
ADG is nothing more than Oracle charging you money for something you already have up and running in Data Guard.
Hi msberg,1 person found this helpful
If the user makes sure ADG is not used, then there is no license issue:
before missusing the Oracle forums to promote another product, think about what you are writing. Shareplex is a technology comparable with GoldenGate and not with Data Guard (or Active Data Guard).
While GoldenGate and Shareplex definitely have their advantages while doing DB upgrades etc, Physical Data Guard (and with this Active Data Guard) is build for disaster recovery, in which area it by far exceeds any possibility you have with other products:
=> Does Shareplex provide Automatic Block repair?
This is one of the greatest features of ADG, since it will automatically detect a corrupt block on the primary or standby site, and instead of giving back an ORA-600 to the user doing a query, it will automatically repair the block in the background.
=> Does Shareplex support all Data Types like the Anytype or any other Object Relational data type (e.g. Media Types, Spatial Data Types, just to name a few)? ADG does.
=> Does Shareplex allow a backup of the Standby and the restore of the primary with it? ADG is physical Data Guard and is 100% block identical to the primary. And with ADG you even get fast incremental backups on the Standby site.
=> And by far the most important: Do you get any support from Oracle if your primary fails, and your Standby setup via. Shareplex does not work?
ADG provides a lot of add on feature you don't have with a standard Data Guard environment.
Hi,1 person found this helpful
forgot the most important point:
How difficult is it to setup Active Data Guard?
=> Simply issue an "alter database open" in the Standby system. If you have Data Guard Broker in use, he handles the other 2 necessary steps (stop the MRP and restart the MRP) for you in the background.
Now compare that to setup GG or Shareplex.....