我如何通过SQL中的聚合字段过滤（where子句）

Question

我有以下查询：

 Select Distinct Product, sum(Deals) as TotalDeals
 from Metrics m
 group by Product

我希望将查询更改为仅返回TotalDeals = 0的位置。

在查询中使用where子句的最佳方法是什么（而不是在事实之后过滤掉结果集）

Answer 1

Select Product, TotalDeals
FROM
(
 Select Product, sum(Deals) as TotalDeals
 from Metrics m
 group by Product
)
Where TotalDeals=0

您不需要区分，因为记录按产品分组

或者

Select Product, sum(Deals) as TotalDeals
from Metrics m
group by Product
having sum(Deals) = 0

Answer 2

尝试使用HAVING：

Select Distinct Product, sum(Deals) as TotalDeals 
from Metrics m 
group by Product 
HAVING sum(Deals) = 0

Answer 3

HAVING是过滤聚合字段的子句

   ...
   group by Product
   HAVING sum(Deals) = 0

Answer 4

  Select Product, sum(Deals) as TotalDeals
     from Metrics m
     group by Product
    having sum(Deals)=0

Answer 5

要使其在MySQL数据库中工作，并且不接收错误代码1248：每个派生表必须拥有自己的别名，

此查询：

Select Product, TotalDeals
FROM
(
 Select Product, sum(Deals) as TotalDeals
 from Metrics m
 group by Product
)
Where TotalDeals=0

必须更新以在闭括号后包含 AS 别名，如下所示：

Select Product, TotalDeals
FROM
(
 Select Product, sum(Deals) as TotalDeals
 from Metrics m
 group by Product
) AS t1
Where TotalDeals=0