This figure is a tree depicting the execution plan for the statement in the preceding text.
Step 1, View emp_group_by_deptno, is a clear box that branches to Step 2, Sort (group by), a clear box. Step 2 branches to Step 3, Table Access (by rowid) employees, a shaded box. Step 3 branches to Step 4, Index (range scan) emp_department_ix, a shaded box.