用sql计算商品销售额连续上升的最大天数

可以通过使用SQL窗口函数和自连接来计算商品销售额连续上升的最大天数。假设我们有一个名为"sales"的表，其中包含商品销售的日期和销售额信息。

首先，我们可以使用窗口函数来为每一天计算销售额与前一天的差异。然后，我们可以使用自连接来找到连续上升的最大天数。

下面是一个示例的SQL查询语句：

WITH diff AS (
  SELECT 
    date,
    sales,
    sales - lag(sales) over (ORDER BY date) AS diff
  FROM sales
)
SELECT 
  MAX(DATEDIFF(day, start_date, end_date)) AS max_days
FROM (
  SELECT 
    date AS start_date,
    CASE WHEN diff <= 0 OR diff IS NULL THEN date ELSE NULL END AS end_date,
    ROW_NUMBER() OVER (ORDER BY date) - ROW_NUMBER() OVER (PARTITION BY CASE WHEN diff <= 0 OR diff IS NULL THEN 0 ELSE 1 END ORDER BY date) AS group_id
  FROM diff
) AS subquery
WHERE end_date IS NOT NULL
GROUP BY group_id
ORDER BY max_days DESC
LIMIT 1;

这个查询会返回连续销售额上升的最大天数。

请注意，这只是一个示例查询语句，具体的实现可能会根据你的数据表结构和数据库类型有所不同。你需要根据自己的实际情况进行相应的调整和修改。