sql server 获取当月的销售额，与去年同期相比，并计算出增长率

首先，你需要有一张表，记录每笔销售的日期和销售额。然后，你可以使用以下 SQL 语句来获取当月的销售额：

SELECT SUM(sales) FROM table WHERE MONTH(date) = MONTH(CURRENT_TIMESTAMP) AND YEAR(date) = YEAR(CURRENT_TIMESTAMP);

如果你想获取去年同期的销售额，可以使用以下语句：

SELECT SUM(sales) FROM table WHERE MONTH(date) = MONTH(CURRENT_TIMESTAMP) AND YEAR(date) = YEAR(CURRENT_TIMESTAMP) - 1;

最后，你可以使用以下语句计算增长率：

SELECT (current_sales - previous_sales) / previous_sales * 100 AS growth_rate FROM (
  SELECT SUM(sales) AS current_sales FROM table WHERE MONTH(date) = MONTH(CURRENT_TIMESTAMP) AND YEAR(date) = YEAR(CURRENT_TIMESTAMP)
) a, (
  SELECT SUM(sales) AS previous_sales FROM table WHERE MONTH(date) = MONTH(CURRENT_TIMESTAMP) AND YEAR(date) = YEAR(CURRENT_TIMESTAMP) - 1
) b;

这样就可以计算出当月销售额与去年同期相比的增长率了。