Explain plan window, changing optimizer goal sometimes does not update explain plan

[Claus Pedersen]

I have a little complex select in the explain plan window. When I update the optimizer goal from e.g. Choose to Rule, it does not seem like the explain grid is updated.
Nothing changes in the grid, e.g. the columns cost, cardinality, and bytes that are normally empty when using Rule, are still filled in.

Example for the user HR:

SELECT SUM(CASE WHEN EXISTS (SELECT NULL
                             FROM   departments dep_aux
                             WHERE  EXISTS (SELECT  NULL
                                            FROM    departments
                                            LEFT OUTER JOIN employees USING (department_id)
                                            WHERE   department_id      = dep_aux.department_id
                                           )
                            ) THEN employees.salary END
          )
FROM   employees

(this is a rewritten bare minimum of the the original select using tables on the HR user, so the select itself gives no meaning, it is just an example).

When I press F5 to get an explain plan, the explain plan for e.g. Rule and Choose are the same and they should not be.

This is also an issue in version 14. Is this an error in PLD or in the Oracle database? Or does everything work as expected?

When I comment out e.g. the left outer join, everything works as expected (as far as I can see).

I am using beta 5 and Oracle Database 18c Express Edition Release 18.0.0.0.0

 

[Marco Kalter]

We'll check it out.