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RAC Database Backups

In 11gR2 Grid Infrastructure and RACIn a RAC environment, the database backups can be executed from any one node or distributed across multiple nodes of the cluster.In my two-node environment, I have...

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Index Growing Larger Than The Table

Here is a very simple demonstration of a case where an Index can grow larger than the table.  This happens because the pattern of data deleted and inserted doesn't allow deleted entries to be reused....

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EXECUTE Privilege on DBMS_SPM not sufficient

In 11.2.0.2Here is a quick demo to show that the "ADMINISTER SQL MANAGEMENT OBJECT" privilege is required for a non-DBA user to use DBMS_SPM even if EXECUTE has been granted on DBMS_SPM.SQL> create...

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The ADMINISTER SQL MANAGEMENT OBJECT Privilege

In 11.2.0.2Having seen in the previous post, "EXECUTE Privilege on DBMS_SPM not sufficient", let's see if there is a risk to the ADMINISTER SQL MANAGEMENT OBJECT privilege.First, recreating the SQL...

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11g Adaptive Cursor Sharing --- does it work only for SELECT statements ?...

Test run in 11.2.0.2UPDATE 07-Oct-14 : I have been able to get the DML statement also to demonstrate Adaptive Cursor Sharing with the "BIND_AWARE" hint as suggested by Stefan Koehler and Dominic...

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Bandwidth and Latency

Here is, verbatim, an article I posted on Linked-In yesterday  [For other posts on Linked-In, view my Linked-In profile] :Imagine an 8-lane highway. Now imagine a 4-lane highway. Which has the greater...

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StatsPack and AWR Reports -- Bits and Pieces -- 1

I am planning to put up a few posts on snippets from StatsPack and AWR reports.  This is my first post. Note : Some figures / details may be slightly changed / masked to hide the real source.Logical...

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StatsPack and AWR Reports -- Bits and Pieces -- 2

This is the second post in a series on reading StatsPack and AWR reports.(The first is available here)Comparing Reports :Here are two 9.2 StatsPack extracts from one database:Extract A  : 9.2...

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StatsPack and AWR Reports -- Bits and Pieces -- 3

This is the third post in this series.Post 1 is herePost 2 is hereNote : Some figures / details may be slightly changed / masked to hide the real source.Identifying Unusual Events / Behaviours /...

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StatsPack and AWR Reports -- Bits and Pieces -- 4

This is the fourth post in a series.Post 1 is here.Post 2 is here.Post 3 is here.Buffer Cache Hit RatiosMany novice DBAs may use Hit Ratios as indicators of performance.  However, these can be...

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Statistics on this blog

I began this blog on 28-Dec-2006.  For the 8 years 2007 to 2014, I have averaged 56 posts per year.  Unfortunately, this year, 2014 has produced the fewest posts -- 40 including this one.  This...

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Inserting into a table with potentially long rows

Note :  This post builds on blog posts by Nikolay Savvinov and Jonathan Lewis.Nikolay Savvinov and Jonathan Lewis have identified that when you have a table with a potentially large row size -- where...

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A blog on Oracle Standard Edition

Here's a blog on Oracle Standard Edition by Ann Sjokvist....

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Database Flashback -- 1

A first post on Database Flashback.Enabling Database Flashback in 11.2 non-RACSQL*Plus: Release 11.2.0.2.0 Production on Sun Feb 1 23:13:17 2015Copyright (c) 1982, 2010, Oracle. All rights...

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Database Flashback -- 2

Continuing my series on Oracle Database Flashback.(My first post on this topic was a week ago).I create a Restore Point :[oracle@localhost Hemant]$ sqlplus '/ as sysdba'SQL*Plus: Release 11.2.0.2.0...

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Database Flashback -- 3

Continuing my series on Oracle Database FlashbackAs I pointed out in my previous post, the ability to flashback is NOT strictly specified by db_flashback_retention_target.  The actual scope may be...

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Database Flashback -- 4

Continuing my series on Oracle Database Flashback.[oracle@localhost Hemant]$ sqlplus '/ as sysdba'SQL*Plus: Release 11.2.0.2.0 Production on Tue Feb 17 22:30:53 2015Copyright (c) 1982, 2010, Oracle....

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Database Flashback -- 5

Continuing my series on Database Flashback.Here I demonstrate that Flashback Logs alone are not sufficient.  The process of FLASHBACK DATABASE does need *some* redo entries from Archive/Online Redo...

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Parallel Execution -- 1 The PARALLEL Hint and AutoDoP

The behaviour of the PARALLEL Hint has changed subtly but significantly in 11.2.  From the documentation : Beginning with Oracle Database 11g Release 2 (11.2.0.1), the PARALLEL and NO_PARALLEL hints...

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Parallel Execution -- 1b The PARALLEL Hint and AutoDoP (contd)

Continuing the previous thread, having restarted the database again, with the same CPU_COUNT and missing I/O Calibration statistics  ....The question this time is : What if the table level DoP is...

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