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Method R Discussion Group

Is it possible to when the clustering factor increases on index which factor can generate this?

I think the question is how the clustering factor number is calculated by the optimizer and how it influences the choice of explain plans.

You should probably read Chapter 5 of Jonathan Lewis's book on Cost Based Optimizer Fundamentals.

The clustering factor kicks in when the optimizer is evaluating a range scan on a B-Tree index. Clustering factor is a number and it indicates how the data is distributed in a table and tells whether doing a range scan and going to the table will be more expensive than doing a table scan.

Thanks for your answer, but which causes set increase the clustering factor? Insert and update statement without the order clause set in  the index for example, Can be that a cause for the increment the clustering factor?
Thanks a lot in advance.
regards,

Alberto Frosi