Hive Installation and use

Hive is a client that uses a similar SQL statement to operate a file stored in HDFs, a data warehouse that needs to be used in conjunction with a relational database, and hive comes with a relational database derby, but it's not officially recommended, and we use MySQL here. The function of relational database is to make the data structure of HDFS, and to correspond the structure and map.

MySQL is used to store mapping relationships, and HDFs is used to store data

First, install MySQL

Slightly

Second, hive installation

1) Extract Hive

tar -zxvf apache-hive-1.0. 1-bin. tar. gz

2) Generate Hive-site.xml

CP Hive-default.xml.template Hive-site.xml

3) Create the specified path and user name

① creates the specified path, replacing the value System:java.io.tmpdir in Hive-site.xml

mkdir /home/whu/hadoop-hive/hive-1.0. 1-bin/iotmp

Replace the value of System:java.io.tmpdir in Hive-site.xml

② Create the specified user name folder under the folder above

cd/home/whu/hadoop-hive/hive-1.0. 1-bin/iotmpmkdir WHU

Replace the value of System:user.name in Hive-site.xml

4) Create a database in MySQL

Mysql-u root-p

Create a specified database

Create DATABASE hive;

5) Modify Hive-site.xml

① Modifying a specified relational database

<property>    <name>javax.jdo.option.ConnectionURL</name>    <value>jdbc:mysql:/ /localhost:3306/hive</value></property>

② Modifying the driver

<property>    <name>javax.jdo.option.ConnectionDriverName</name>    <value> Com.mysql.jdbc.driver</value></property>

③ Modifying the user name of the connection database

<property>    <name>javax.jdo.option.ConnectionUserName</name>    <value>root</ Value></property>    

Note: Because my test environment hive and MySQL are installed on a machine, there is no set root for remote login, if MySQL and hive are not on a single machine, you need to configure root or other users to log on remotely

Grant all on * * to [email protected]'%'root';

④ Modifying the password of the connection database

<property>    <name>javax.jdo.option.ConnectionPassword</name>    <value>root</ Value></property>

6) Copy the MySQL driver to the Lib directory of Hive

CP mysql-connector-java-5.1. -bin.jar  /home/whu/soft/apache-hive/lib

Note: If the MySQL drive is not in the correct version, it will cause the deletion of the table to fail, so it is more appropriate to release the MySQL drive.

7) Start Hive

Add hive to an environment variable first

Export Hadoop_home=/home/whu/soft/apache-hive
Export Path= $HADOOP _home:bin

Make environment variables effective

Source/etc/profile

Start Hive

Hive

Third, Hive simple use

1) Display Database

show databases;

2) Display Data sheet

Use database;show tables;

3) Create a database

Create Database basename;

4) Delete Database

basename;

5) Create a table

' /001 ' stored as textfile;

6) Delete Table

if exists tablename;

7) Upload Data

' Path ' into table tablename;

8) inserting data

INSERT into TABLE tablename1 [PARTITION (Partcol1=val1, Partcol2=val2 ...)] select_statement1 from From_statement;

　

Hive Installation and use