Spark2 Dataset聚合操作
data.groupBy("gender").agg(count($"age"),max($"age").as("maxAge"), avg($"age").as("avgAge")).show ...
原文：Spark2 Dataset之視圖與SQL
創建視圖 data.createOrReplaceTempView Affairs val df spark.sql SELECT FROM Affairs WHERE age BETWEEN AND df : org.apache.spark.sql.DataFrame affairs: double, gender: string ... more fields 子查詢 val df spa ...
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