Spark之HiveSupport連線（spark-shell和IDEA）

本文介紹了使用Spark連線Hive的兩種方式，spark-shell和IDEA遠端連線。

1.spark-shell

1.1.拷貝配置檔案

1. 拷貝hive/conf/hdfs-site.xml 到 spark/conf/ 下
2. 拷貝hive/lib/mysql 到 spark/jars/下
   這裡可以通過如下引數來實現指定jar-path

--driver-class-path path/mysql-connector-java-5.1.13-bin.jar

1.2.啟動spark-shell

spark.sql("show databases").show()
spark.sql("use test")
spark.sql("select * from student").show()

執行結果：

[hadoop@hadoop1 spark-2.3.0-bin-hadoop2.7]$ ./bin/spark-shell
2018-09-04 11:43:10 WARN  NativeCodeLoader:62 - Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Setting default log level to "WARN".
To adjust logging level use sc.setLogLevel(newLevel). For SparkR, use setLogLevel(newLevel).
Spark context Web UI available at http://hadoop1:4040
Spark context available as 'sc' (master = local[*], app id = local-1536032600945).
Spark session available as 'spark'.
Welcome to
      ____              __
     / __/__  ___ _____/ /__
    _\ \/ _ \/ _ `/ __/  '_/
   /___/ .__/\_,_/_/ /_/\_\   version 2.3.0
      /_/

Using Scala version 2.11.8 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_91)
Type in expressions to have them evaluated.
Type :help for more information.

scala> spark.sql("show databases").show()
2018-09-04 11:43:54 WARN  ObjectStore:568 - Failed to get database global_temp, returning NoSuchObjectException
+------------+
|databaseName|
+------------+
|     default|
|        test|
+------------+


scala> spark.sql("use test")
res1: org.apache.spark.sql.DataFrame = []

scala> spark.sql("select * from student").show()
+----+-----+---+----+-----+
| sno|sname|sex|sage|sdept|
+----+-----+---+----+-----+
|1001|   張三|  男|  22|   高一|
|1002|   李四|  女|  25|   高二|
+----+-----+---+----+-----+

2.IDEA連線Hive

這裡是連線遠端的Hive，如果還沒有部署Hive，請參考Hive之環境安裝，前提是必須先啟動hdfs。

2.1.引入依賴

<!-- https://mvnrepository.com/artifact/org.apache.spark/spark-core -->
<dependency>
  <groupId>org.apache.spark</groupId>
  <artifactId>spark-core_2.11</artifactId>
  <version>2.3.0</version>
  <!--<scope>provided</scope>-->
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.spark/spark-sql_2.11 -->
<dependency>
  <groupId>org.apache.spark</groupId>
  <artifactId>spark-sql_2.11</artifactId>
  <version>2.3.0</version>
  <!--<scope>provided</scope>-->
</dependency>
<dependency>
  <groupId>org.apache.spark</groupId>
  <artifactId>spark-hive_2.11</artifactId>
  <version>2.3.0</version>
</dependency>
<dependency><!--資料庫驅動：Mysql-->
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>5.1.40</version>
</dependency>

2.2.拷貝配置檔案

拷貝hive-site.xml到專案的resources目錄下即可

<configuration>
  <property>
    <name>javax.jdo.option.ConnectionURL</name>
    <value>jdbc:mysql://hadoop1:3306/hive?createDatabaseIfNotExist=true</value>
    <description>JDBC connect string for a JDBC metastore</description>
  </property>
  
  <property>
    <name>javax.jdo.option.ConnectionDriverName</name>
    <value>com.mysql.jdbc.Driver</value>
    <description>Driver class name for a JDBC metastore</description>
  </property>
  
  <property>
    <name>javax.jdo.option.ConnectionUserName</name>
    <value>root</value>
    <description>username to use against metastore database</description>
  </property>
  
  <property>
    <name>javax.jdo.option.ConnectionPassword</name>
    <value>root</value>
    <description>password to use against metastore database</description>
  </property>
</configuration>

2.3.編寫程式碼

object HiveSupport {
  def main(args: Array[String]): Unit = {
    //val warehouseLocation = "D:\\workspaces\\idea\\hadoop"

    val spark =
      SparkSession.builder()
        .appName("HiveSupport")
        .master("local[2]")
        //拷貝hdfs-site.xml不用設定，如果使用本地hive，可通過該引數設定metastore_db的位置
        //.config("spark.sql.warehouse.dir", warehouseLocation)
        .enableHiveSupport() //開啟支援hive
        .getOrCreate()

    //spark.sparkContext.setLogLevel("WARN") //設定日誌輸出級別
    import spark.implicits._
    import spark.sql

    sql("show databases")
    sql("use test")
    sql("select * from student").show()

    Thread.sleep(150 * 1000)
    spark.stop()
  }
}

執行結果：

+----+-----+---+----+-----+
| sno|sname|sex|sage|sdept|
+----+-----+---+----+-----+
|1001|   張三|  男|  22|   高一|
|1002|   李四|  女|  25|   高二|
+----+-----+---+----+-----+

參考：

1. Spark的spark.sql.warehouse.dir相關
2. Spark 2.2.1 + Hive
3. spark連線hive（spark-shell和eclipse兩種方式）
4. 官方文件