mysql if示例
1 SELECT IF(ed.id IS NULL, '0', ed.id) id, IF(ed.name IS NULL, '其他', ed.name) name, COUNT(up.uid) memberCount, IF(ed.create_time IS NULL, NOW(), ed.create_time) create_time FROM user_profile up 2 LEFT JOIN enterprise_departments_users edu ON up.uid = edu.uid 3 LEFT JOIN enterprise_department ed ON edu.department_id = ed.id 4 WHERE up.enterprise_id = ? GROUP BY ed.top_id, ed.create_time ORDER BY ed.create_time ASC;