select pvi.*,
(select rc.reagent_consumable_name
from reagent_consumables rc
where rc.reagent_consumable_id = pvi.reference_material_id) as reference_material_name,
(SELECT user.name
FROM dlp_base.sys_user user
WHERE user.user_id=pvi.inspector_id ) as inspector_nam
, (
SELECT user.name
FROM dlp_base.sys_user user
WHERE user.user_id=pvi.technical_director_id ) as technical_director_name
FROM period_verification_implementation pvi