The Final Word

  • Stelios Charalambides


The key to successful tuning with SQLT is to use SQLT regularly and for real-life problems. If you’ve reached the final chapter, you should now consider yourself a card-carrying member of the SQLT supporters club. You’ve learned a lot about what SQLT can do, and along the way you’ve probably learned some things about the cost-based optimizer and the Oracle engine. Let me remind you of some of the features we came across on our journey:
  • The effect of statistics on execution plans

  • The effect of skewness on execution plans

  • How the optimizer transforms SQL during parsing

  • How profiles can help you temporarily freeze an execution plan

  • How adaptive cursor sharing works

  • How dynamic sampling works

  • How cardinality feedback works

  • How you can use SQLT with Data Guard

  • How test cases can be built with SQLT to allow exploration of the execution plans

  • How to use the brute force of XPLORE to look for unexpected effects on the CBO from upgrades and other changes.

  • How we can use the COMPARE method to investigate two SQLs

  • Last but not least we talked about the health check script, which is a good second choice if SQLT is not available.


Final Word Execution Plan Final Chapter Dynamic Sampling Tuning Problem 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Stelios Charalambides 2013

Authors and Affiliations

  • Stelios Charalambides

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