hive是基于Hadoop的一个数据仓库工具,可以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,可以将sql语句转换
引言: Hive是一种强大的数据仓库查询语言,,类似SQL,本文将介绍如何搭建Hive的开发测试环境。
1. 什么是Hive?
hive是基于Hadoop的一个数据仓库工具,可以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,可以将sql语句转换为MapReduce任务进行运行。 其优点是学习成本低,可以通过类SQL语句快速实现简单的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. 按照Hive的准备条件
2.1 Hadoop集群环境已经安装完毕
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目录下
tar xzvf apache-hive-0.13.1-bin.tar.gz
3.3 设置环境变量
export HIVE_HOME=/opt/apache-hive-0.13
export PATH=$PATH:$HIVE_HOME/bin
export CLASSPATH=$CLASSPATH:$HIVE_HOME/bin
3.4. 修改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 修改hive-site.xml,主要修改数据库的连接信息.
基于Hadoop集群的Hive安装
Hive内表和外表的区别
Hadoop + Hive + Map +reduce 集群安装部署
Hive本地独立模式安装
Hive学习之WordCount单词统计
3.6 安装mysql数据库
sudo apt-get install mysql-server
3.7 创建
3.8 在
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