Spark SQL 笔记(5)—— Hive 到 Spark SQL（1）

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/u012292754/article/details/83618343

1 SQLContext

1.1 Spark1.x 中Spark SQL 的入口点：SQLContext

参考链接 https://spark.apache.org/docs/1.6.1/sql-programming-guide.html#starting-point-sqlcontext

1.2 测试案例

1.2.1 新建maven 工程

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.tzb.demo2</groupId>
    <artifactId>SQLContext</artifactId>
    <version>1.0</version>
    <inceptionYear>2008</inceptionYear>
    <properties>
        <scala.version>2.11.8</scala.version>
        <spark.version>2.1.0</spark.version>
    </properties>

    <repositories>
        <repository>
            <id>scala-tools.org</id>
            <name>Scala-Tools Maven2 Repository</name>
            <url>http://scala-tools.org/repo-releases</url>
        </repository>
    </repositories>

    <pluginRepositories>
        <pluginRepository>
            <id>scala-tools.org</id>
            <name>Scala-Tools Maven2 Repository</name>
            <url>http://scala-tools.org/repo-releases</url>
        </pluginRepository>
    </pluginRepositories>

    <dependencies>
        <dependency>
            <groupId>org.scala-lang</groupId>
            <artifactId>scala-library</artifactId>
            <version>${scala.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.spark</groupId>
            <artifactId>spark-sql_2.11</artifactId>
            <version>${spark.version}</version>
        </dependency>

    </dependencies>

    <build>
        <sourceDirectory>src/main/scala</sourceDirectory>
        <testSourceDirectory>src/test/scala</testSourceDirectory>
        <plugins>
            <plugin>
                <groupId>org.scala-tools</groupId>
                <artifactId>maven-scala-plugin</artifactId>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                            <goal>testCompile</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <scalaVersion>${scala.version}</scalaVersion>
                    <args>
                        <arg>-target:jvm-1.5</arg>
                    </args>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-eclipse-plugin</artifactId>
                <configuration>
                    <downloadSources>true</downloadSources>
                    <buildcommands>
                        <buildcommand>ch.epfl.lamp.sdt.core.scalabuilder</buildcommand>
                    </buildcommands>
                    <additionalProjectnatures>
                        <projectnature>ch.epfl.lamp.sdt.core.scalanature</projectnature>
                    </additionalProjectnatures>
                    <classpathContainers>
                        <classpathContainer>org.eclipse.jdt.launching.JRE_CONTAINER</classpathContainer>
                        <classpathContainer>ch.epfl.lamp.sdt.launching.SCALA_CONTAINER</classpathContainer>
                    </classpathContainers>
                </configuration>
            </plugin>
        </plugins>
    </build>
    <reporting>
        <plugins>
            <plugin>
                <groupId>org.scala-tools</groupId>
                <artifactId>maven-scala-plugin</artifactId>
                <configuration>
                    <scalaVersion>${scala.version}</scalaVersion>
                </configuration>
            </plugin>
        </plugins>
    </reporting>
</project>

1.2.2 源码

数据

package com.tzb

import org.apache.spark.sql.SQLContext
import org.apache.spark.{SparkConf, SparkContext}

object SQLContextApp {
  def main(args: Array[String]): Unit = {

    def main(args: Array[String]): Unit = {

      val path = args(0)

      val conf = new SparkConf()
      conf.setAppName("SQLContextApp").setMaster("local[2]")
      val sc = new SparkContext(conf)

      val sqlContext = new SQLContext(sc)

      val people =  sqlContext.read.format("json").load(path)
      people.printSchema()
      people.show()

      sc.stop()

    }
  }
}

1.2.3 运行结果

1.3 打包运行在集群

启动集群

[hadoop@node1 ~]$ /home/hadoop/apps/spark-2.1.3-bin-2.6.0-cdh5.7.0/sbin/start-all.sh

[hadoop@node1 spark-2.1.3-bin-2.6.0-cdh5.7.0]$ ./bin/spark-submit --class com.tzb.demo2.SQLContextApp --master local[2] /home/hadoop/SQLContext-1.0.jar /home/hadoop/people.json