PostgreSQL is an open-source database server similar (but different) than MySQL. cPanel has a built-in installer for setting up PostgreSQL easily. Keep in mind that the actual version of PostgreSQL you get depends on your OS version. For instance, CentOS 4 users will likely get version 7, CentOS 5 will get version 8.
First, run the install script from command line
Then in WHM under SQL Services >> Postgres Config Choose Install Config. Once the config has been installed set a root password for PostgreSQL (Only Alphanumerics). If you hav a firewall, you may want to open port 5432.
PostgreSQL is installed now, but PHP is not compiled for it, so you'll need to run EasyApache and enable PHP with PostgreSQL (pgsql) support. You can do this manually, or through WHM. If doing so manually, here is the configure switch (or use with /var/cpanel/easy/apache/custom/rawopts [La Magie De La Reconquête – The Magic Of Making Up French Version