7. [Optional] Install MySQL

If you are installing Hive and HCatalog services, you need a MySQL database instance to store metadata information. You can either use an existing MySQL instance or install a new instance of MySQL manually. To install a new instance:

Connect to the host machine you plan to use for Hive and HCatalog.
Install MySQL server. From a terminal window, type:
For RHEL/CentOS:
```
yum install mysql-server
```
Start the instance.
```
/etc/init.d/mysqld start
```

Set the root user password.

mysqladmin -u root -p‘{password}’ password $mysqlpassword

Remove unnecessary information from log and STDOUT.
```
mysqladmin -u root 2>&1 >/dev/null
```

As root, use mysql (or other client tool) to create the “dbuser” and grant it adequate privileges. This user provides access to the Hive metastore.

CREATE USER '$dbusername'@'localhost' IDENTIFIED BY '$dbuserpassword';
GRANT ALL PRIVILEGES ON *.* TO 'dbuser'@'localhost';
CREATE USER 'dbuser'@'%' IDENTIFIED BY 'dbuserpassword';
GRANT ALL PRIVILEGES ON *.* TO 'dbuser'@'%';
FLUSH PRIVILEGES;

See if you can connect to the database as that user. You are prompted to enter the $dbuserpassword password above.
```
mysql -u dbuser -p $dbuserpassword
```

Install the MySQL connector JAR file.

For RHEL/CentOS/Oracle Linux:
```
yum install mysql-connector-java*
```
For SLES:
```
zypper install mysql-connector-java*
```
For Ubuntu:
```
apt-get install mysql-connector-java*
```

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