業務需求:
最近的問題就是，有很多部門，部門又擁有商品，商品有不同的品種，我們需要計算出不同部門裡有多少不同商品，
但是對乙個部門來說 既有屬於部門的商品，也有屬於個人的商品，這也就是兩個表，
首先，我們知道，我們需要查的就是部門中同乙個商品，個人持有量和部門持有量。
select
ri_equipmentmessage_sparepart.id,
ri_equipmentmessage_sparepart.`name`,
ri_equipmentmessage_sparepart.model,
ri_equipmentmessage_sparepart.brand,
ri_equipment_sparepart.sparepart_number as number,
ri_equipmentmessage_equipment.department
from
ri_equipment_sparepart
inner join ri_equipmentmessage_sparepart on ri_equipment_sparepart.sparepart_id = ri_equipmentmessage_sparepart.id
inner join ri_equipmentmessage_equipment on ri_equipment_sparepart.equipment_id = ri_equipmentmessage_equipment.id
union all
select
ri_equipmentmessage_sparepart.id,
ri_equipmentmessage_sparepart.`name`,
ri_equipmentmessage_sparepart.model,
ri_equipmentmessage_sparepart.brand,
ri_department_sparepart.number,
ri_department_sparepart.departmentid as department
from
ri_department_sparepart
inner join ri_equipmentmessage_sparepart on ri_department_sparepart.sparepartid = ri_equipmentmessage_sparepart.id
select
id,name,
model,
brand,
sum(number),
department
from
( select
ri_equipmentmessage_sparepart.id,
ri_equipmentmessage_sparepart.`name`,
ri_equipmentmessage_sparepart.model,
ri_equipmentmessage_sparepart.brand,
ri_equipment_sparepart.sparepart_number as number,
ri_equipmentmessage_equipment.department
from
ri_equipment_sparepart
inner join ri_equipmentmessage_sparepart on ri_equipment_sparepart.sparepart_id = ri_equipmentmessage_sparepart.id
inner join ri_equipmentmessage_equipment on ri_equipment_sparepart.equipment_id = ri_equipmentmessage_equipment.id
union all
select
ri_equipmentmessage_sparepart.id,
ri_equipmentmessage_sparepart.`name`,
ri_equipmentmessage_sparepart.model,
ri_equipmentmessage_sparepart.brand,
ri_department_sparepart.number,
ri_department_sparepart.departmentid as department
from
ri_department_sparepart
inner join ri_equipmentmessage_sparepart on ri_department_sparepart.sparepartid = ri_equipmentmessage_sparepart.id
) as a
group by
department,
id
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