下面是一个示例语句: WITH a AS (SELECT * FROM scott.emp), b AS (SELECT * FROM scott.dept) SELECT a.deptno, b.dname, a.empno, a.ename FROM a, b WHERE a.deptno = b.deptno ORDER BY a.deptno, a.empno; 使用WITH子句有时可以简化FROM子句的复杂性。