Fix survey invitations report for surveys with same code in different courses (when using code, the c_id and session_id are necessary) - refs BT#15280

main/survey/survey.lib.php

@@ -1806,7 +1806,10 @@ class SurveyManager
                 $tblSurvey = Database::get_course_table(TABLE_SURVEY);
 
                 $sql = "SELECT i.user FROM $tblInvitation i
-                    INNER JOIN $tblSurvey s ON i.survey_code = s.code
+                    INNER JOIN $tblSurvey s 
+                    ON i.survey_code = s.code
+                        AND i.c_id = s.c_id
+                        AND i.session_id = s.session_id
                     WHERE i.answered IS TRUE AND s.iid = $survey_id";
             }
         }

main/survey/surveyUtil.class.php

@@ -3881,6 +3881,7 @@ class SurveyUtil
                 ON (survey_invitation.user = user.id AND survey_invitation.c_id = $courseId)
                 WHERE
                     survey_invitation.survey_code = '$surveyCode'
+                    AND survey_invitation.c_id = $courseId
                     $sessionCondition";
 
         $query = Database::query($sql);