This is the default example configuration of pgsql provided by Postfix. This config file was generated by Postfix running on CentOS 8.
It is located under: /etc/postfix/postfix-files.d/pgsql
$shlib_directory/postfix-pgsql.so:f:root:-:755
$manpage_directory/man5/pgsql_table.5.gz:f:root:-:644
$readme_directory/PGSQL_README:f:root:-:644
Download the raw file with wget or curl
wget -O pgsql.example http://exampleconfig.com/static/raw/postfix/centos8/etc/postfix/postfix-files.d/pgsql
curl http://exampleconfig.com/static/raw/postfix/centos8/etc/postfix/postfix-files.d/pgsql > pgsql.example
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