引言: Hive是一种强大的数据仓库查询语言,类似SQL,本文将介绍怎样搭建Hive的开发測试环境。
1. 什么是Hive?
hive是基于Hadoop的一个数据仓库工具,能够将结构化的数据文件映射为一张数据库表,并提供简单的sql查询功能,能够将sql语句转换为MapReduce任务进行执行。 其长处是学习成本低,能够通过类SQL语句高速实现简单的MapReduce统计。不必开发专门的MapReduce应用,十分适合数据仓库的统计分析。
2. 依照Hive的准备条件
2.1 Hadoop集群环境已经安装完成
2.2 本文使用Ubuntu做为开发环境(14.04)
3. 安装步骤
3.1 下载Hive包:apache-hive-0.13.1-bin.tar.gz
3.2 将其解压到/opt文件夹下
tar xzvf apache-hive-0.13.1-bin.tar.gz
3.3 环境变量设置
export HIVE_HOME=/opt/apache-hive-0.13
export PATH=$PATH:$HIVE_HOME/bin
export CLASSPATH=$CLASSPATH:$HIVE_HOME/bin
3.4. 改动hive-env.xml,复制hive-env.xml.template.
# Set HADOOP_HOME to point to a specific hadoop install directory
HADOOP_HOME=/opt/hadoop-1.2.1
# Hive Configuration Directory can be controlled by:
export HIVE_CONF_DIR=/opt/apache-hive-0.13/conf
3.5 改动hive-site.xml,主要改动数据库的连接信息.
<property> <name>hive.metastore.uris</name> <value>thrift://127.0.0.1:9083</value> <description>Thrift URI for the remote metastore. Used by metastore client to connect to remote metastore.</description> </property> <property> <name>javax.jdo.option.ConnectionURL</name> <value>jdbc:mysql://BladeStone-Laptop: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>hive</value> <description>username to use against metastore database</description> </property> <property> <name>javax.jdo.option.ConnectionPassword</name> <value>123456</value> <description>password to use against metastore database</description> </property>
3.6 安装mysql数据库(Ubuntu系统)
sudo apt-get install mysql-server
3.7 创建mysql用户hive
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3.8 在mysql中创建hive数据库
3.9 下载mysql驱动,并将驱动拷贝到hive_home/lib类库
mysql-connector-java-5.1.31-bin.jar
3.10 启动Hive
3.11 在Hive中创建表
3.12 登录mysql。訪问hive数据库
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3.13 删除Hive中的表
3.14 登录mysql,查询TBLS中的数据
4. 总结
通过以上的步骤,我们完整的安装了一个Hive,并通过加入和删除一张数据库表的演示,来展示了Hive和Mysql元数据库之间的关系操作。
5. 常见问题
5.1 直接通过hive命令来启动,则会出现一下错误信息:
Logging initialized using configuration in jar:file:/opt/apache-hive-0.13/lib/hive-common-0.13.1.jar!/hive-log4j.properties Exception in thread "main" java.lang.RuntimeException: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.metastore.HiveMetaStoreClient at org.apache.hadoop.hive.ql.session.SessionState.start(SessionState.java:346) at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:681) at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:625) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:483) at org.apache.hadoop.util.RunJar.main(RunJar.java:160) Caused by: java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.metastore.HiveMetaStoreClient at org.apache.hadoop.hive.metastore.MetaStoreUtils.newInstance(MetaStoreUtils.java:1412) at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.<init>(RetryingMetaStoreClient.java:62) at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:72) at org.apache.hadoop.hive.ql.metadata.Hive.createMetaStoreClient(Hive.java:2453) at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:2465) at org.apache.hadoop.hive.ql.session.SessionState.start(SessionState.java:340) ... 7 more Caused by: java.lang.reflect.InvocationTargetException at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:408) at org.apache.hadoop.hive.metastore.MetaStoreUtils.newInstance(MetaStoreUtils.java:1410) ... 12 more Caused by: MetaException(message:Could not connect to meta store using any of the URIs provided. Most recent failure: org.apache.thrift.transport.TTransportException: java.net.ConnectException: Connection refused at org.apache.thrift.transport.TSocket.open(TSocket.java:185) at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.open(HiveMetaStoreClient.java:336) at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.<init>(HiveMetaStoreClient.java:214) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:408) at org.apache.hadoop.hive.metastore.MetaStoreUtils.newInstance(MetaStoreUtils.java:1410) at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.<init>(RetryingMetaStoreClient.java:62) at org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(RetryingMetaStoreClient.java:72) at org.apache.hadoop.hive.ql.metadata.Hive.createMetaStoreClient(Hive.java:2453) at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:2465) at org.apache.hadoop.hive.ql.session.SessionState.start(SessionState.java:340) at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:681) at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:625) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:483) at org.apache.hadoop.util.RunJar.main(RunJar.java:160) Caused by: java.net.ConnectException: Connection refused at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:345) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at java.net.Socket.connect(Socket.java:589) at org.apache.thrift.transport.TSocket.open(TSocket.java:180) ... 19 more ) at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.open(HiveMetaStoreClient.java:382) at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.<init>(HiveMetaStoreClient.java:214) ... 17 more
解决的方法: hive --service metastore , 用这条命令来启动hive。
5.2 配置 hive.metastore.uris
a.不启动metastore和hiveserver服务
直接命令行hive进入hive shell环境。然后运行show databases 报错例如以下:
ERROR ql.Driver: FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask. java.lang.RuntimeException: Unable to instantiate org.apache.hadoop.hive.metastore.HiveMetaStoreClient
b.另外一种种情况
1.配置 hive.metastore.uris
2.启动metastore服务 hive --service metastore
然后直接命令行hive进入hive shell环境,然后运行show databases
c:第三种情况
1.凝视配置项 hive.metastore.uris
2.不启动metastore服务
然后直接命令行hive进入hive shell环境。然后运行show databases