employee.employee_name FROM employee LEFT JOIN salary USING( employee_id ) WHERE salary.salary_amount IS NULL
常兩個欄位名稱相同時可以USING 不同時可以ON 例如: employee.employee_name FROM employee LEFT JOIN salary ON employee.employee_id=salary.employee_id WHERE salary.salary_amount IS NULL ------------------------------------ 歡迎光臨偶像劇場∠(^_^)