代码大概如下
select *, ((case when 入库 is null then 0 else 入库 end)-(case when 出库 is null then 0 else 出库 end)) as 库存 from (select Distinct 产品名称,产品批号,产品入仓piao面价,产品入仓成本价,产品分类,产品所属部门,仓库名称,(select sum(产品数量) from {库存明细表} b where a.产品名称=b.产品名称 and a.产品批号=b.产品批号 and a.产品入仓piao面价=b.产品入仓piao面价 and a.产品分类=b.产品分类 and a.产品所属部门=b.产品所属部门 and a.仓库名称=b.仓库名称 and 入出库存类型='入库') as 入库,(select sum(产品数量) from {库存明细表} b where a.产品名称=b.产品名称 and a.产品批号=b.产品批号 and a.产品入仓piao面价=b.产品入仓piao面价 and a.产品分类=b.产品分类 and a.产品所属部门=b.产品所属部门 and a.仓库名称=b.仓库名称 and 入出库存类型='出库') as 出库 from {库存明细表} a) as c