Package: zabbix-server-pgsql

"zabbix-server-pgsql" package binaries on CentOS:

/usr/sbin/zabbix_server_pgsql

You may install this package on CentOS with yum install zabbix-server-pgsql

"zabbix-server-pgsql" package binaries on Debian:

/usr/bin/zabbix_get /usr/sbin/zabbix_server

You may install this package on Debian with apt-get install zabbix-server-pgsql