Set up a PostgreSQL database

You install a Postgres database to serve as the backend database for the Hive metastore. You also install the Postgres driver on your cluster, and then configure the database.

  1. Install the database from the command line of a node in your cluster.
    • RHEL:
      sudo yum install postgresql-server
    • SLES:
      sudo zypper install postgresql-server
    • Ubuntu:
      sudo apt-get install postgresql
  2. If your system is RHEL, initialize database files; otherwise, skip this step.
    sudo service postgresql initdb
  3. Set the listen_addresses property to * and set the standard_conforming_strings property off.
    • RHEL and SLES:
      sudo cat /var/lib/pgsql/data/postgresql.conf  | grep -e listen -e standard_conforming_strings
      listen_addresses = '*'
      standard_conforming_strings = off
    • Ubuntu:
      cat /etc/postgresql/9.1/main/postgresql.conf | grep -e listen -e standard_conforming_strings
      listen_addresses = '*'
      standard_conforming_strings = off
  4. Add a new line into pg_hba.con to ensure that the Postgres user can access the server remotely.
    For example, to allow all users to connect from all hosts to all your databases:
    host  <database>  <user>  <network address>  <mask>   md5
    This configuration is applicable only for a network listener. Using this configuration does not open all your databases to the entire world; you must provide a password to authenticate yourself, and privilege restrictions configured in PostgreSQL are effective.
  5. Start the Postgres server.
    sudo service postgresql start
  6. Set Postgres to start when the cluster comes up, and check the configuration.
    chkconfig postgresql on
    chkconfig --list postgresql
  7. On the Hive metastore server node in your cluster, install the latest Postgres JDBC driver (the postgresql-jdbc package), and create symbolic link to the /usr/lib/hive/lib/ directory.
    • RHEL
      sudo yum install postgresql-jdbc
      ln -s /usr/share/java/postgresql-jdbc.jar /usr/lib/hive/lib/postgresql-jdbc.jar
    • SLES
      sudo zypper install postgresql-jdbc
      ln -s /usr/share/java/postgresql-jdbc.jar /usr/lib/hive/lib/postgresql-jdbc.jar
    • Ubuntu
      sudo apt-get install libpostgresql-jdbc-java
      ln -s /usr/share/java/postgresql-jdbc4.jar /usr/lib/hive/lib/postgresql-jdbc4.jar
  8. Create a metastore database and user account to access the metastore, using the script for your Hive version represented by n.n.n.
    sudo -u postgres psql
    postgres=# CREATE USER hiveuser WITH PASSWORD 'mypassword';
    postgres=# CREATE DATABASE metastore;
    postgres=# \c metastore;
    You are now connected to database 'metastore'.
    postgres=# \i /usr/lib/hive/scripts/metastore/upgrade/postgres/hive-schema-n.n.n.postgres.sql