用 DataFusion 窗口函数排名与填补空值

原文许可与版权声明

Apache DataFusion 贡献者的窗口函数文档及其中代码按 Apache License 2.0 提供。以下原许可头逐字保留。本文为中文翻译，编校补充已单独标示，修改日期为 2026-10-05。Pokémon 示例数据来源：Ritchie Vink。

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