I submitted an instance of a questionnaire and then selected the 'All your responses' tab.

All the questions after the second question are displayed as '2', which seems strange.

As the editing teacher I selected the 'All responses (1)' tab

This resulted in some error code and strange display.

(Some of the questions in this questionnaire were given the same name,and the user making the response exists in multiple groups).

The code displayed is:

Did you remember to make the first column something unique in your call to get_records? Duplicate value '1' found in column 'id'.
line 699 of /lib/dml/pgsql_native_moodle_database.php: call to debugging()
line 163 of /mod/questionnaire/report.php: call to pgsql_native_moodle_database->get_records_sql()
Did you remember to make the first column something unique in your call to get_records? Duplicate value '1' found in column 'id'.

I have fixed this and attach a patch for review.