CentOS/RHEL Open Source CPU with Yum

This is an end-to-end recipe for installing OmniSci Open Source on a CentOS/RHEL 7 machine running without GPUs using Yum.

Here is a quick video overview of the installation process.

https://youtu.be/dQRCcSt3Z44youtu.be

The order of these instructions is significant. To avoid problems, install each component in the order presented.

Assumptions

These instructions assume the following:

• You are installing on a “clean” CentOS/RHEL 7 host machine with only the operating system installed.

• Your OmniSci host only runs the daemons and services required to support OmniSci.

• Your OmniSci host is connected to the Internet.

Preparation

Prepare your host machine by updating your system and creating the OmniSci user.

Update and Reboot

Update the entire system and reboot to activate the latest kernel.

sudo yum update
sudo reboot

Create the OmniSci User

Create a group called omnisci and a user named omnisci, who will be the owner of the OmniSci database. You can create the group, user, and home directory using the useradd command with the -U and -m switches.

sudo useradd -U -m omnisci

Installation

Create a repo file at /etc/yum.repos.d/omnisci.repo with the OmniSci repository specification:

[omnisci]
name='omnisci os - cpu'
baseurl=https://releases.omnisci.com/os/yum/stable/cpu
enabled=1
gpgcheck=1
repo_gpgcheck=0
gpgkey=https://releases.omnisci.com/GPG-KEY-mapd

Use the following yum command to install OmniSci.

sudo yum install omnisci

Configuration

These are the steps to prepare your OmniSci environment.

Set Environment Variables

For convenience, you can update .bashrc with the required environment variables.

1. Open a terminal window.

2. Enter cd ~/ to go to your home directory.

3. Open .bashrc in a text editor. For example, vi .bashrc.

4. Edit the .bashrc file. Add the following export commands under “User specific aliases and functions.”

   # User specific aliases and functions
   export OMNISCI_USER=omnisci
   export OMNISCI_GROUP=omnisci
   export OMNISCI_STORAGE=/var/lib/omnisci
   export OMNISCI_PATH=/opt/omnisci
   export OMNISCI_LOG=/var/lib/omnisci/data/mapd_log

5. Save the .bashrc file.

6. Open a new terminal window to use your changes.

The $OMNISCI_STORAGE directory must be dedicated to OmniSci: do not set it to a directory shared by other packages.

Initialization

Run the systemd installer.

cd $OMNISCI_PATH/systemd
./install_omnisci_systemd.sh

Accept the values provided (based on your environment variables) or make changes as needed. The script creates a data directory in $OMNISCI_STORAGE with the directories mapd_catalogs, mapd_data, and mapd_export. mapd_import and mapd_log directories are created when you insert data the first time. If you are an OmniSci administrator, the mapd_log directory is of particular interest.

Activation

Start and use OmniSciDB.

1. Start OmniSciDB.

   sudo systemctl start omnisci_server

2. Enable OmniSciDB to start automatically when the system reboots.

   sudo systemctl enable omnisci_server

Checkpoint

To verify that everything is working correctly, load some sample data, and perform an omnisql query.

1. OmniSci ships with two sample datasets of airline flight information collected in 2008, and a census of New York City trees. To install sample data, run the following command.

   cd $OMNISCI_PATH
   sudo ./insert_sample_data

2. When prompted, choose dataset 2 (10 thousand rows).

   Enter dataset number to download, or 'q' to quit:
   #     Dataset           Rows    Table Name          File Name
   1)    Flights (2008)    7M      flights_2008_7M     flights_2008_7M.tar.gz
   2)    Flights (2008)    10k     flights_2008_10k    flights_2008_10k.tar.gz
   3)    NYC Tree Census (2015)    683k    nyc_trees_2015_683k    nyc_trees_2015_683k.tar.gz

3. Connect to OmniSciDB by entering the following command (default password is HyperInteractive):

   $OMNISCI_PATH/bin/omnisql
   password: ••••••••••••••••

4. Enter a SQL query such as the following, based on dataset 2 above:

   omnisql> SELECT origin_city AS "Origin", dest_city AS "Destination", AVG(airtime) AS
   "Average Airtime" FROM flights_2008_10k WHERE distance < 175 GROUP BY origin_city,
   dest_city;

   The results should be similar to the results below.

   Origin|Destination|Average Airtime
   Austin|Houston|33.055556
   Norfolk|Baltimore|36.071429
   Ft. Myers|Orlando|28.666667
   Orlando|Ft. Myers|32.583333
   Houston|Austin|29.611111
   Baltimore|Norfolk|31.714286