sql - 如何将 Count 与 Max 函数和 Group By 一起使用

Question

我在下面使用此查询来获取过时帐户的列表，但我想尝试计算返回的行数而不是完整列表，但我被卡住并寻求帮助。

SELECT customer_name, MAX(order_date) AS last_Sale_Date
FROM sales_history
GROUP BY customer_name
HAVING max(order_date) <= '01/01/2017 23:59:59'

标签： sqlsql-servertsql

Answer 1

你可以使用：

SELECT TOP 1 COUNT(*) OVER()
FROM sales_history
GROUP BY customer_name
HAVING max(order_date) <='01/01/2017 23:59:59';

DBFiddle 演示