Logical and Physical Standby Practice

Hello Gurus
I am now attempting to practice Oracle Data Guard and in this direction I understand since 10g we have logical standby server as well as a physical standby server. While I am gathering information and knowledge about the data guard as is and varisous modes and types possible with oracle 10g and 11g in specific, an attempt to upgrade my self and learn these set-ups and understand them in detail.. I come to you for some guidence..
I am referring to Oracle Documentation for these details. At the same time I also approach you to share your experiences .. may be a link apart from the documentation of oracle which you might want to refer me to use as a quick reference.. some thing that a person like me .. fairly new to this set-up understand it and then attempt to come up with one..
This is for my practise and learning purpose.
Sarat.

Logical Standby was already introduced in 9i. It differs from physical standby in the way, the redo protocol, transmitted from the primary, gets used to actualize the standby. With logical standby, you have SQL APPLY - basically, we try to generate the same SQL that was done on the primary from the redo protocol that was written on behalf of that SQL on the primary. That SQL then is done on the OPEN instance at the logical standby.
In case of a physical standby, the redo protocol from the primary is used to do RECOVERY - called REDO APPLY - to actualize the standby.
Since 10g, the sames protection levels can be achieved with logical or physical standby.
Drawback of logical standby: Not all kinds of SQL and all datatypes are supported
Drawback of physical standby: It is mounted (versions before 11g) while being recoverd - or in 11g, REDO APPLY in READ ONLY status is possible but comes with an extra charge (ACTIVE DATA GUARD feature).
If you look on my Blog, I have some examples about creating physical & logical standby DBs
Kind regards
Uwe
http://uhesse.wordpress.com

Similar Messages

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    Is it possible to have a logical and physical standby database for a primary database on the same node (i.e. primary on NodeA, logical and physical database of primary on NodeB)?
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    From a technical point of view this is possible. Your standby node should be powerful enough to handle 2 instances. For even higher availability 3 dedicated nodes would be better. When Node B is down, both physical and logical standby are also down.
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  • Logica and Physical standby to the same Primary?

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  • Configuring both logical and physical standby databases.

    Hi,
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    ALPER ONEY
    email:[email protected]

    Hi,
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  • Downtime for logical or physical standby database

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    Hi Richard,
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  • What is a  Logical and Physical file path in sap?

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  • Logical and physical file paths

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    hi,
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  • Data guard synchronization after link down b/w primary and physical standby

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  • Diff between logical and physical file path

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    Save your changes.

  • Diff  between logical and physical page ?

    hi
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  • Importing logical and physical model from Sybase power designer/Erwin

    Hello,
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  • Can I check whole DB for logical and physical consistency?

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    Asif Momen
    http://momendba.blogspot.com

  • Diff logical and physical doc

    Hello BW Experts,
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    hi BWer,
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    http://help.sap.com/saphelp_nw2004s/helpdata/en/6c/69bd22418d11d1896e0000e8322d00/frameset.htm
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  • Issueduring verifying logical and physical dependencies of tablespaces.

    I am facing below issue with Transportable Tablespace during verifying logical and physical dependencies of two tablespaces.
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    SQL*Plus: Release 10.2.0.2.0 - Production on Sat Oct 7 07:46:07 2006
    Copyright (c) 1982, 2005, Oracle. All Rights Reserved.
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    Here i face another issue relates to transporting tablespace.
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    5> 'C:\tmpdir\tmpdir\tw_04.dbf',
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    using channel ORA_DISK_2
    using channel ORA_DISK_3
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    using channel ORA_DISK_5
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    RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
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    Source database is 10.1.0.3.0 and target database is 10.1.0.2.0. Does it matter?
    Message was edited by:
    GK Joe

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