Hi,

The Estimator part of Cost-Based Optimizer, generates three types of measures: selectivity, cardinality and cost.
I want to know, in the execution plan of a SQL statement in PL/SQL Developer (so when we press F5), how can we add the selectivity column? At Settings, I don't see a selectivity column, but there are those of Cost and Cardinality.

How can we see the selectivity of a particular SQL statement?

Thank you.

I don't see a selectivity column in the official PLAN_TABLE:
http://docs.oracle.com/cd/E16655_01/server.121/e15858/tgsql_interp.htm#TGSQL94734

You are right