This figure is a tree depicting the execution plan for the statement in the preceding text.
Step 1, Nested Loops, is a clear box that branches to Step 2, View emp_group_by_deptno, a clear box, and Step 5, Table Access (by rowid) deartments, a shaded box. Step 2 branches to Step 3, Sort (group by), a clear box. Step 3 branches to Step 4, Table Access (full) employees, a shaded box. Step 5 branches to Step 6, Index (unique scan) dept_id_pk, a shaded box.