LEFT JOIN (select m.* from wl_equipment_specific_index m left join wl_equipment_index e on e.id = m.equipment_index_id where e.is_iot = 1) b ON a.id = b.equipment_specific_id
RIGHT JOIN (select m.* from wl_equipment_specific_index m left join wl_equipment_index e on e.id = m.equipment_index_id where e.is_iot = 1) b ON a.id = b.equipment_specific_id