org.apache.spark.sql.TypedColumn Java Examples
The following examples show how to use
org.apache.spark.sql.TypedColumn.
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Example #1
Source File: JavaUserDefinedTypedAggregation.java From incubator-nemo with Apache License 2.0 | 5 votes |
/** * Main function. * * @param args arguments. */ public static void main(final String[] args) { SparkSession spark = SparkSession .builder() .appName("Java Spark SQL user-defined Datasets aggregation example") .getOrCreate(); Encoder<Employee> employeeEncoder = Encoders.bean(Employee.class); String path = args[0]; Dataset<Employee> ds = spark.read().json(path).as(employeeEncoder); ds.show(); // +-------+------+ // | name|salary| // +-------+------+ // |Michael| 3000| // | Andy| 4500| // | Justin| 3500| // | Berta| 4000| // +-------+------+ MyAverage myAverage = new MyAverage(); // Convert the function to a `TypedColumn` and give it a name TypedColumn<Employee, Double> averageSalary = myAverage.toColumn().name("average_salary"); Dataset<Double> result = ds.select(averageSalary); result.show(); // +--------------+ // |average_salary| // +--------------+ // | 3750.0| // +--------------+ spark.stop(); }
Example #2
Source File: Dataset.java From incubator-nemo with Apache License 2.0 | 5 votes |
@Override public <U1> Dataset<U1> select(final TypedColumn<T, U1> c1) { final boolean userTriggered = initializeFunction(c1); final Dataset<U1> result = from(super.select(c1)); this.setIsUserTriggered(userTriggered); return result; }
Example #3
Source File: JavaUserDefinedTypedAggregation.java From nemo with Apache License 2.0 | 5 votes |
/** * Main function. * @param args arguments. */ public static void main(final String[] args) { SparkSession spark = SparkSession .builder() .appName("Java Spark SQL user-defined Datasets aggregation example") .getOrCreate(); Encoder<Employee> employeeEncoder = Encoders.bean(Employee.class); String path = args[0]; Dataset<Employee> ds = spark.read().json(path).as(employeeEncoder); ds.show(); // +-------+------+ // | name|salary| // +-------+------+ // |Michael| 3000| // | Andy| 4500| // | Justin| 3500| // | Berta| 4000| // +-------+------+ MyAverage myAverage = new MyAverage(); // Convert the function to a `TypedColumn` and give it a name TypedColumn<Employee, Double> averageSalary = myAverage.toColumn().name("average_salary"); Dataset<Double> result = ds.select(averageSalary); result.show(); // +--------------+ // |average_salary| // +--------------+ // | 3750.0| // +--------------+ spark.stop(); }
Example #4
Source File: Dataset.java From nemo with Apache License 2.0 | 5 votes |
@Override public <U1> Dataset<U1> select(final TypedColumn<T, U1> c1) { final boolean userTriggered = initializeFunction(c1); final Dataset<U1> result = from(super.select(c1)); this.setIsUserTriggered(userTriggered); return result; }
Example #5
Source File: UDFExample.java From Apache-Spark-2x-for-Java-Developers with MIT License | 4 votes |
public static void main(String[] args) { //Window Specific property if Hadoop is not instaalled or HADOOP_HOME is not set System.setProperty("hadoop.home.dir", "E:\\hadoop"); //Build a Spark Session SparkSession sparkSession = SparkSession .builder() .master("local") .config("spark.sql.warehouse.dir","file:///E:/hadoop/warehouse") .appName("EdgeBuilder") .getOrCreate(); Logger rootLogger = LogManager.getRootLogger(); rootLogger.setLevel(Level.WARN); // Read the CSV data Dataset<Row> emp_ds = sparkSession.read() .format("com.databricks.spark.csv") .option("header", "true") .option("inferSchema", "true") .load("src/main/resources/employee.txt"); UDF2 calcDays=new CalcDaysUDF(); //Registering the UDFs in Spark Session created above sparkSession.udf().register("calcDays", calcDays, DataTypes.LongType); emp_ds.createOrReplaceTempView("emp_ds"); emp_ds.printSchema(); emp_ds.show(); sparkSession.sql("select calcDays(hiredate,'dd-MM-yyyy') from emp_ds").show(); //Instantiate UDAF AverageUDAF calcAvg= new AverageUDAF(); //Register UDAF to SparkSession sparkSession.udf().register("calAvg", calcAvg); //Use UDAF sparkSession.sql("select deptno,calAvg(salary) from emp_ds group by deptno ").show(); // TypeSafeUDAF typeSafeUDAF=new TypeSafeUDAF(); Dataset<Employee> emf = emp_ds.as(Encoders.bean(Employee.class)); emf.printSchema(); emf.show(); TypedColumn<Employee, Double> averageSalary = typeSafeUDAF.toColumn().name("averageTypeSafe"); Dataset<Double> result = emf.select(averageSalary); result.show(); }