남는건 기록뿐

Check SCHEMA data.printSchema Check COLUMNS data.columns SELECT val pracData = data.select($"fecha_dato", $"ncodpers", $"ind_empleado") //change schema, name of columns pracData.select($"fecha_dato".cast("timestamp") as "Date", $"ncodpers".cast("string") as "CutomerNum", $"ind_empleado".cast("string") as "employed") // change only a name of a column pracData.withColumnRenamed("Date", "DateTime")..

Download binary cd /path/to/spark/download wget http://apache.mirror.cdnetworks.com/spark/spark-3.0.0-preview2/spark-3.0.0-preview2-bin-hadoop3.2.tgz. tar zxvf spark-3.0.0-preview2-bin-hadoop3.2.tgz ln -s spark-3.0.0-preview2-bin-hadoop3.2 default Setting Environment Variables export SPARK_HOME="/path/to/spark/download/default" export SPARK_CONF_DIR="${SPARK_HOME}/conf" export PATH="${PATH}:${SP..