Complete output off this function for me is:
array(13) {
["client"]=>
string(5) "9.6.9"
["protocol"]=>
int(3)
["server"]=>
string(4) "12.1"
["server_encoding"]=>
string(4) "UTF8"
["client_encoding"]=>
string(4) "UTF8"
["is_superuser"]=>
string(2) "on"
["session_authorization"]=>
string(8) "postgres"
["DateStyle"]=>
string(8) "ISO, MDY"
["IntervalStyle"]=>
string(8) "postgres"
["TimeZone"]=>
string(10) "US/Arizona"
["integer_datetimes"]=>
string(2) "on"
["standard_conforming_strings"]=>
string(2) "on"
["application_name"]=>
string(0) ""
}