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Jonathan Lewis' presentation on Smarter Statistics in 11g

User_UOVAAJun 18 2013 — edited Jun 21 2013

After viewing Jonathan Lewis' excellent presentation, ( http://www.speak-tech.com/lewis-20130610 ) the main thing

I got out of it was to set the 'approximate_ndv' to true and to avoid using histograms.

So, I checked my global preferences and confirmed they were set to the default values, specifically:

SNAME               SPARE4

------------------- ----------------------------

APPROXIMATE_NDV     FALSE

METHOD_OPT          FOR ALL COLUMNS SIZE AUTO


So, by Jonathan's presentation, I will set APPROXIMATE_NDV to TRUE.

But my question is in regards to METHOD_OPT:  Should I, (or would it be safe)

to set the global_prefs for this to "FOR ALL COLUMNS SIZE 1".


This would basically eliminate all histograms (eventually when it updates statistics), including any that Oracle uses on its own internal tables.


This post has been answered by Jonathan Lewis on Jun 21 2013
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