#file1: read as $conf_file1
{
   db => {
            name => 'pdte',
            host => 'localhost',
         }
}
#file2: read as $conf_file2
{   
   db => {
             port => '5432',
             user => 'pdte_usr',
             password => 'pdte_213456',
         }
}

my $new_conf = { %$conf_file1, %conf_file2 }