yum install -y epel-release
For other RHEL-based distribution, see the EPEL documentation.

yum install -y postgresql-server
postgresql-setup initdb
systemctl enable postgresql
systemctl start postgresql
yum-config-manager –add-repo=https://nightly.odoo.com/9.0/nightly/rpm/odoo.repo
yum install -y odoo
systemctl enable odoo
systemctl start odoo