如何在FlinkSQL中实现多维分析(OLAP)场景的窗口操作？

-- 每5分钟统计过去1小时的累计销售额，按地区和产品下钻
SELECT 
  HOP_START(event_time, INTERVAL '5' MINUTE, INTERVAL '1' HOUR) AS hop_window,
  region,
  product_id,
  SUM(amount) AS cumulative_sales
FROM sales_events
GROUP BY 
  HOP(event_time, INTERVAL '5' MINUTE, INTERVAL '1' HOUR),
  region,
  product_id;

-- 按小时、地区、产品类别统计销售额
SELECT 
  TUMBLE_START(event_time, INTERVAL '1' HOUR) AS hour_window,
  region,
  product_category,
  SUM(amount) AS total_sales
FROM sales_events
GROUP BY 
  TUMBLE(event_time, INTERVAL '1' HOUR),
  region,
  product_category;