Spark posexplode_outer(e: Column) creates a row for each element in the array and creates two columns “pos’ to hold the position of the array element and the ‘col’ to hold the actual array value. Posexplode_outer – explode array or map columns to rows. posexplode – array exampleĭf.select($"name",posexplode($"knownLanguages"))ĭf.select($"name",posexplode($"properties")) Since the Washington and Jefferson have null or empty values in array and map, the following snippet out does not contain these. This will ignore elements that have null or empty. And when the input column is a map, posexplode function creates 3 columns “pos” to hold the position of the map element, “key” and “value” columns. Posexplode(e: Column) creates a row for each element in the array and creates two columns “pos’ to hold the position of the array element and the ‘col’ to hold the actual array value. Posexplode – explode array or map elements to rows explode_outer – array exampleĭf.select($"name",explode_outer($"knownLanguages"))ĭf.select($"name",explode_outer($"properties")) Unlike explode, if the array or map is null or empty, explode_outer returns null. Spark SQL explode_outer(e: Column) function is used to create a row for each element in the array or map column. When a map is passed, it creates two new columns one for key and one for value and each element in map split into the row.Įxplode_outer – Create rows for each element in an array or map. When an array is passed to this function, it creates a new default column “col1” and it contains all array elements. Spark function explode(e: Column) is used to explode or create array or map columns to rows. Val df = spark.createDataFrame((arrayData),arraySchema)Įxplode – spark explode array or map column to rows add("properties", MapType(StringType,StringType)) add("knownLanguages", ArrayType(StringType)) #Scala cannot resolve overloaded method map how to#Before we start, let’s create a DataFrame with array and map fields, below snippet, creates a DF with columns “name” as StringType, “knownLanguage” as ArrayType and “properties” as MapType.Īnd, from below code, “spark” is an instance of SparkSession, please refer to complete code at the end to see how to create SparkSession object.
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