官方介绍
Hive执行流程图：

【Pratical Hive.pdf】学习笔记，各章节做主线辅以官网资料整理完成。

组件架构

• 客户端组件
  Hive-cli,
  JDBC/ODBC
  Toad or SQuirreL

• HCatalog
  元数据管理组件，主要作用如下
  官方介绍
  • Provides a common schema environment for multiple tools
  • Allows for connectors to tools to read data from and write data to Hive’s warehouse
  • Lets users share data across tools
  • Creates a relational structure to Hadoop data
  • Abstracts away the how and where of data storage
  • Hides schema and storage changes from users

• hiveServer2
  接口服务组件

• Execution-Engine

• MR
  执行引擎组件

• Tez
  执行引擎组件，省略shuffle过程
  Tez avoids disk IO by avoiding expensive shuffle and shorts while leveraging more efficient map side joins. Tez also utilizes a costbased optimizer, which helps produce faster execution plans. Combine this with the ORC file format geared
  toward SQL performance and you have a query engine performing up to 100x faster than native MapReduce–

• Hive-on-Spark

• Storage: Hadoop
  基于hdfs文件存储