Question

我有3张桌子：

客户（姓名，身份证），
项目（名称，价格，ID），
购买（id，items_id，customers_id）

当我跑步时：

select 
 customers.name,
 SUM(items.price) as "price"
from items
INNER JOIN purchases
ON items.id = purchases.item_id
INNER JOIN customers
ON purchases.customer_id = customers.id
GROUP BY customers.name
ORDER BY "price"

这是我得到的结果：

"Anne Watson" "5.00"
"Craig Scott" "11.30"
"Michael Adam" "101.29"
"Jose Salvatierra" "899.00"
"Rolf Smith" "1174.50"

但是，我想只显示那些价格超过100的行（在这种情况下为3个底部行）。我怎么能这样做？

Answer 1

这是您使用HAVING子句的地方。它与WHERE子句类似，但在GROUP BY之后应用。

HAVING SUM(items.price) > 100

Answer 2

如果您只想要大于100的SUM（价格）包含如下的HAVING子句。

select 
 customers.name,
 SUM(items.price) as "price"
from items
INNER JOIN purchases
ON items.id = purchases.item_id
INNER JOIN customers
ON purchases.customer_id = customers.id
GROUP BY customers.name
having sum(items.price) >100

Answer 3

这是WHERE函数的解决方案

select 
   customers.name,
   SUM(items.price) as price
from items, purchases, customers
where 
   items.id = purchases.item_id and purchases.customer_id = customers.id and 
   items.price > 100

GROUP BY customers.name
ORDER BY price;

仅显示SUM（价格）超过特定数量

3 个答案: