GROUPBY 和开窗函数执行顺序的问题

  SELECT seller_id FROM 
(SELECT seller_id , RANK() OVER(ORDER BY SUM(price) DESC) AS r
FROM Sales GROUP BY seller_id) s
WHERE s.r=1;

作者：SunnyCCCh
链接：https://leetcode.cn/problems/sales-analysis-i/solutions/868818/partition-by-he-group-by-de-shi-yong-qu-nts8m/
来源：力扣（LeetCode）
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。    

SELECT seller_id FROM 
(SELECT seller_id , RANK() OVER(PARTITION BY seller_id ORDER BY SUM(price) DESC) AS r
FROM Sales ) s
WHERE s.r=1;

作者：SunnyCCCh
链接：https://leetcode.cn/problems/sales-analysis-i/solutions/868818/partition-by-he-group-by-de-shi-yong-qu-nts8m/
来源：力扣（LeetCode）
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。


--案例1  这个案例等于是将  
  
SELECT SELLER_ID ,
         SUM(PRICE),
         DENSE_RANK() OVER( ORDER BY  SUM(PRICE) DESC ) RN --不分区. 留意最下面有group by ，groupby级别高于开窗函数计算顺序这个是重点.
FROM SALES A
GROUP BY  SELLER_ID


--如下结果：

| seller_id | sum(price) | dense_rank() over(  order by sum(price) desc ) |
| --------- | ---------- | ---------------------------------------------- |
| 1         | 2800       | 1                                              |
| 3         | 2800       | 1                                              |
| 2         | 800        | 2                                              |