来自诸如this和this之类的问题，当我将在RDD级别上分区的数据帧保存到（例如）镶木桌子。
或者也许换句话说：spark.rdd.compress是否还会压缩我使用spark.rdd.compress时创建的表？
spark.rdd.compress来自docs，执行以下操作：
是否压缩序列化的RDD分区（例如 Java和Scala中的StorageLevel.MEMORY_ONLY_SER或 Python中的StorageLevel.MEMORY_ONLY）。 可以节省大量空间 花费一些额外的CPU时间。压缩将使用 spark.io.compression.codec。
因此，此外，如果这种压缩有效，是否还会花费额外的CPU从这种表中再次检索数据？
答案 0 :(得分：1)
spark.rdd.compress是否还会压缩我使用dataframe.write.saveAsTable（...）时创建的表
不会，RDD接收器也不会。
如您引用的文档中所述，它仅适用于序列化（$(function () {
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）缓存。它与外部存储无关。