A big data engineer can transform data stored in files using Sparkdataframemethods or Spark SQLfunctions. I chose to use the Spark SQL syntax since it is more widely used. Every language has at least three core data types: strings, numbers, and date/time. How do we manipulatestringsusing S...
DataFrame:spark ML从spark sql中获取DataFrame作为学习的数据集。可以持有多种数据类型 ,例如:有个df可以包含文本,特征向量,true标签和预测结果的多个不同的列。 转换器: 转换器是把一个DF转成另外一个DF的算法,例:一个ML模型是一个转换器 ,转换带有特征的DataFrame成为带有预测结果的DF. 评估器: 评估器是应用(...
bin/spark-submit --class org.apache.spark.examples.sql.hive.JavaSparkHiveExample --master spark://192.168.1.110:7077 --executor-memory 10G --total-executor-cores 6 /home/sparksql.jar 计算结果如下,部分。 17/05/27 15:34:11 INFO CodeGenerator: Code generated in 8.29917 ms +---+---+--...
scala> val df=spark.read.format("json").load("file:///opt/software/spark-2.2.0-bin-2.6.0-cdh5.7.0/examples/src/main/resources/people.json") df: org.apache.spark.sql.DataFrame = [age: bigint, name: string] df.printSchema root |-- age: long (nullable = true) |-- name: string...
Spark SQL Examples Spark SQL FunctionsShow More What is Spark SQL? Spark SQL is one of the main components of the Apache Spark framework. It is mainly used for structured data processing. It provides various Application Programming Interfaces (APIs) in Python, Java, Scala, and R. Spark SQL...
Spark SQL Array Function Scala Examples Before we use these functions, let’s create a DataFrame with a few array columns. I will use this DataFrame for all my examples below. // Import import org.apache.spark.sql.SparkSession // Create SparkSession ...
Spark Core Spark SQL Spark Streaming Spark MLlib Spark GraphXSpark Modules Spark CoreIn this section of the Apache Spark Tutorial, you will learn different concepts of the Spark Core library with examples in Scala code. Spark Core is the main base library of Spark which provides the ...
[root@master soft]# cd hive-1.2.1/ [root@master hive-1.2.1]# ls bin examples lib NOTICE RELEASE_NOTES.txt tmp conf hcatalog LICENSE README.txt scripts [root@master hive-1.2.1]# pwd /usr/local/soft/hive-1.2.1 [root@master hive-1.2.1]# cd conf/ [root@master conf]# ls beeline...
.appName("Java Spark SQL basic example") .config("spark.some.config.option", "some-value") .getOrCreate(); 在Spark repo的“examples/src/main/java/org/apache/spark/examples/sql/JavaSparkSQLExample.java”中可以找到完整的示例代码。 Spark 2.0中的SparkSession提供了对Hive特性的内置支持,包括使用Hi...
Summary In this chapter, we explored how to use tabular data with Spark SQL. These code examples can be reused as the foundation for processing data with Spark SQL. In another chapter, we use the same data with DataFrames for predicting taxi fares....