countif和sumif每行没有分组

Question

我试图使用SQL

找出sumif和countif

以下是开始的代码：        SELECT
      项目ID     ，供应商     ，成本     ， 销售价格     来自countifExpirement

我试图创建此输出：

前四列已有数据，我试图创建计算字段来计算重复项目，每个供应商的项目和供应商的成本。 易于创建excel。有很多例子可以使用分组方法，但我需要每一行都存在。

Answer 1

在标准SQL中，您将使用分析函数。但是，它们并非在每个DBMS中都可用。

select 
  itemid, supplier, cost, saleprice, 
  count(*) over (partition by itemid) as count_itemid, 
  count(*) over (partition by supplier) as count_supplier, 
  sum(cost) over (partition by supplier) as cost_suppler
from countifexpirement;

这与子选择相同，在每个DBMS中都可用：

select 
  itemid, supplier, cost, saleprice, 
  (
    select count(*) 
    from countifexpirement x 
    where x.itemid = countifexpirement.itemid
  ) as count_itemid, 
  (
    select count(*) 
    from countifexpirement x 
    where x.supplier = countifexpirement.supplier
  ) as count_supplier, 
  (
    select sum(cost)
    from countifexpirement x 
    where x.supplier = countifexpirement.supplier
  ) as cost_suppler
from countifexpirement;