Home » Oracle » 1z0-117 » Which three statements are true about the execution of this query?
View the code sequence:
Which three statements are true about the execution of this query?
A. The optimizer uses an index join as an access path.
B. The optimizer uses a B* tree access path for the EMPLOYEES table.
C. The optimizer uses a bitmap access path for the EMPLOYEES table.
D. The optimizer performs bitmap conversion fromrow IDs.
E. The optimizer performs bitmap conversion to row IDs of the combined maps.
F. The optimizer performs bitmap conversion from the row IDs of the combined maps.
Correct Answer: ACF
Explanation/Reference:
C:The INDEX_COMBINE hint explicitly chooses a bitmap access path for the table.
F:If you specify indexspec, then the optimizer tries to use some Boolean combination of the specified indexes. Each parameter serves the same purpose as in "INDEX Hint". For example:
SELECT /*+ INDEX_COMBINE(e emp_manager_ix emp_department_ix) */ *
FROM employees e
WHERE manager_id = 108
OR department_id = 110;
Download Printable PDF. VALID exam to help you PASS.
|
|