Dontcheff

Oracle teaching Oracle

In Grid Control, SQL on July 22, 2010 at 17:09

Interesting enough, often we rely on the same component to improve the SQL statement that could not generate an optimal plan in the first place. I am talking about the Cost Based Optimizer. Look at this. Note that the database in question is an active database.

So, top SQL is one being generated by Grid Control. So far so good. Let’s run the SQL Tuning Advisor and have a look at the recommendations:

What do we witness? CBO learning from its mistakes? Or Oracle teaching Oracle? Or Oracle learning from Oracle. Whatever…

Interesting recommendation: “Rewrite the predicate into an equivalent form to take advantage of indices”. I wish I could start re-writing the Grid Control code. But I will analyze SYS.LIBRARY$ and accept the profile. Note: in 11g Grid Control, we can implement the profile with forced matching via the GUI, no need to do it any longer in SQL*Plus:

However, I still claim that Oracle Enterprise Manager Grid Control is probably the best feature/tool/utility in Oracle after 9i.

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