Spark2 Dataset行列操作和執行計划
Dataset是一個強類型的特定領域的對象，這種對象可以函數式或者關系操作並行地轉換。每個Dataset也有一個被稱為一個DataFrame的類型化視圖，這種DataFrame是Row類型的Dataset，即Dataset[Row] Dataset是“懶惰”的，只在執行行動操作時觸發計算 ...
原文：Spark2 Dataset聚合操作
data.groupBy gender .agg count age ,max age .as maxAge , avg age .as avgAge .show gender count age maxAge avgAge female . . male . . data.groupBy gender .agg age gt count , age gt max , age gt avg .s ...
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