˰ïæд¸öSQLÓï¾ä Á轨Èñ 26·ÖÖÓǰ Á½ÕÅ±í¹ØÁª ²¿ÃÅ Ô±¹¤ ÒªÇó²é³öÔ±¹¤ÈËÊýСÓÚÈýµÄ ËùÓв¿ÃŵıàºÅºÍÃû³Æ select count(empno),d.dname from emp e,dept d where e.deptno=d.deptno group by d.dname ÕâÊDzé³öÿ¸ö²¿ÃŵÄÈËÊý£¬È»ºó¾Í²»»áÐ´ÄØ¡£ÄÄλÅóÓѰïÒ»ÏÂæ£¡Ð»Ð»ÁË £¡ ¶à¿´Êé 1Â¥ ºÃÓÐÓÄĬ¸Ð°¡¡£Äã¶à¿´¿´Êé°É£¬Ñ§»áÁËÔÙÀ´»Ø´ð¡£ SQL code: SELECT d.deptno, d.dname from dept d, (SELECT d.deptno from emp e, dept d WHERE d.deptno = e.deptno(+) GROUP BY d.deptno HAVING COUNT(1) < 3) a WHERE d.deptno = a.deptno