From http://www.postgresql.org/download/linux/redhat/ comes the following quote:
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Due to policies for Red Hat family distributions, the PostgreSQL installation will not be enabled for automatic start or have the database initialized automatically. To make your database installation complete, you need to perform these two steps:
service postgresql initdb
chkconfig postgresql on
or, on Fedora 19 and other later derived distributions:
postgresql-setup initdb
systemctl enable postgresql.service
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To which policies are they referring? Licensing, security, or other?