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The difference of execution plans [message #398885] Sun, 19 April 2009 01:11
Messages: 3
Registered: April 2009
Junior Member
Hi guys,
I was wondering if there's any difference between the result of:
Method 1:
SQL>explain plan for select * from emp;
SQL>select * from table(dbms_xplan.display(null, null, 'all'));


Method 2:
SQL>alter session set statistics_level=ALL;
SQL>select * from emp;
SQL>select * from table(dbms_xplan.display_cursor(null, null, 'ALLSTATS LAST'));

Except that method 2 provides real information (Actual Rows, Actual Time, etc), is there any difference in the generated plans?

Are they all actual execution plans or only method 2 is providing actual execution plan?

Is there any situation that Method 1 provides different plan with Method 2?
I'm asking this because we might not be able to get enough privileges for running Method 2.


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