【SQL开源代码栏目提醒】:网学会员为广大网友收集整理了,27.6.3.4.2.sql,希望对大家有所帮助!
--使用EXISTS—在父
查询的选择谓词
SELECT /* IN example */
e.employee_id, e.first_name, e.last_name, e.department_id, e.salary
FROM employees e
WHERE e.department_id = 80 /* Note 5 */
AND e.job_id = 'SA_REP' /* Note 6 */
AND e.employee_id IN
(SELECT o.sales_rep_id FROM orders o); /* Note 4 */
SELECT /* EXISTS example */
e.employee_id, e.first_name, e.last_name, e.salary
FROM employees e
WHERE e.department_id = 80 /* Note 5 */
AND e.job_id = 'SA_REP' /* Note 6 */
AND EXISTS (SELECT 1 /* Note 1 */
FROM orders o
WHERE e.employee_id = o.sales_rep_id); /* Note 2 */