由于MYSQL目前只实现了UNION，
所以后面两个就没得玩罗。。。。
SELECT emp_id, assigned_branch_id -> FROM employee -> WHERE title = 'Teller' -> UNION -> SELECT open_emp_id, open_branch_id -> FROM account -> WHERE product_cd = 'SAV' -> ORDER BY emp_id;
由于MYSQL目前只实现了UNION，
所以后面两个就没得玩罗。。。。
SELECT emp_id, assigned_branch_id -> FROM employee -> WHERE title = 'Teller' -> UNION -> SELECT open_emp_id, open_branch_id -> FROM account -> WHERE product_cd = 'SAV' -> ORDER BY emp_id;
