# 高级处理

窗口函数：实现一些聚合函数无法实现的高级功能

```
<􏰌􏰍􏰎􏰏窗口函数> OVER ([PARTITION BY <列清单􏰰􏰱􏰲>]
                                    ORDER BY <􏰳􏰴􏰵􏰰􏰱􏰲排序用列清单>)
```

RANK，记录排序函数

按照不同商品类型，各自按照销售单价排序

![](/files/-LokoShjkv0p80C_DoIt)

```
SELECT product_name,product_type,sale_price,
                RANK() OVER (PARTITION BY product_type
                     ORDER BY sale_price) AS ranking
    FROM Product;
```


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