hive学习官方网站:
General Info
============
For the latest information about Hive, please visit out website at:
http://hive.apache.org/
Getting Started
===============
- Installation Instructions and a quick tutorial:
https://cwiki.apache.org/confluence/display/Hive/GettingStarted
- A longer tutorial that covers more features of HiveQL:
https://cwiki.apache.org/confluence/display/Hive/Tutorial
- The HiveQL Language Manual:
https://cwiki.apache.org/confluence/display/Hive/LanguageManual
1.显示数据库
show databases ;
2.创建数据库
create database db_hive ;
3. 显示表,显示表的详细信息,显示表的详细信息(格式化后),创建表
show tables ;
desc extended student ;
desc formated student ;
create table student(id int, name string) ROW FORMAT DELIMITED FIELDS
TERMINATED BY '\t' ;
4. 装载数据,最好加上数据库名
hive> load data local inpath '/opt/datas/student.txt' into
> table db_hive.student ;
5. 查看函数,查看函数使用方法
show functions ;
desc function upper ;
6. hive中操作文件系统
dfs -ls /user/hive/warehouse ;
dfs -rm -R /user/hive/warehouse/emp;
7. 查看hive的交互命令
hive -help
usage: hive
-d,--define <key=value> Variable subsitution to apply to hive
commands. e.g. -d A=B or --define A=B
--database <databasename> Specify the database to use
-e <quoted-query-string> SQL from command line
例如:[root@zhangbk hadoop]# hive -e 'select * from db_hive.student ;'
-f <filename> SQL from files
例如:vi /opt/datas/hivef.sql
select * from db_hive.student ;
[root@zhangbk datas]# hive -f /opt/datas/hivef.sql
也可将查询结果写入文件:[root@zhangbk datas]# hive -f /opt/datas/hivef.sql > /opt/datas/hivef.txt
-h <hostname> connecting to Hive Server on remote host
-H,--help Print help information
--hiveconf <property=value> Use value for given property
--hivevar <key=value> Variable subsitution to apply to hive
commands. e.g. --hivevar A=B
-i <filename> Initialization SQL file
例如:与用户自定义的udf相互使用。
-p <port> connecting to Hive Server on port number
-S,--silent Silent mode in interactive shell
-v,--verbose Verbose mode (echo executed SQL to the
console)
8. 交互命令hive cli
exit/quit ;
dfs -ls / ;
!ls ;查看操作系统本地的文件