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New Version Of XPLAN_ASH Utility
A new version of the XPLAN_ASH tool (detailed analysis of a single SQL statement execution) is available for download. The previous post includes links to video tutorials explaining what the tool is...
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Analysing Parallel Execution Skew – Video Tutorial
Along the new mini series "Parallel Execution Skew" at "AllThingsOracle.com" that provides some information what you can do if you happen to have a parallel SQL execution that is affected by work...
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Parallel Execution Overhead
I've started a new mini series about "Parallel Execution Skew" at AllThingsOracle.com. In order to avoid bloating the articles too much there I'll post some accompanying notes here on my blog.If you...
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New Version Of XPLAN_ASH Utility
A minor update 4.01 to the XPLAN_ASH utility is available for download.As usual the latest version can be downloaded here.These are the notes from the change log:- More info for RAC Cross Instance...
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Analysing Parallel Execution Skew – Data Flow Operations (DFOs) And DFO Trees
This is the second part of the video tutorial "Analysing Parallel Execution Skew". In this part I introduce the concept of "Data Flow Operations (DFOs)" and "DFO Trees", which is what a Parallel...
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Analysing Parallel Execution Skew – Without Diagnostics / Tuning Pack License
This is the third part of the video tutorial "Analysing Parallel Execution Skew". In this part I show how to analyse a parallel SQL execution regarding Parallel Execution Skew.If you don't have a...
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Parallel Execution Skew – Demonstrating Skew
This is just a short notice that the next part of the mini-series "Parallel Execution Skew" is published at AllThingsOracle.com Related posts: Analysing Parallel Execution Skew – Video Tutorial...
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12c New Optimizer Features
Besides the officially available information about new optimizer features in 12c it is always a good idea to have a look at the internal optimizer parameters that show what features are enabled when...
View Article12c Hybrid Hash Distribution with Skew Detection / Handling
Oracle 12c introduces several new features in the area of Parallel Execution. Over the next couple of weeks I attempt to publish more about them - Jonathan Lewis for example already published a note...
View Article12c Hybrid Hash Distribution with Skew Detection / Handling – Failing
This is just an addendum to the previous post demonstrating one example (out of many possible) where the join skew handling feature fails. The test case setup is the same as in the previous post.As...
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