Improve the speed of the database user retrieval for the student nav.

lib/WeBWorK/ContentGenerator/GatewayQuiz.pm

@@ -1376,9 +1376,13 @@ sub nav ($c, $args) {
 		my $setVersion = $c->{set}->version_id;
 
 		# Find all versions of this set that have been taken (excluding those taken by the current user).
-		my @users =
+		my @userVersions =
 			$db->listSetVersionsWhere({ user_id => { '!=' => $userID }, set_id => { like => "$setID,v\%" } });
-		my @allUserRecords = $db->getUsers(map { $_->[0] } @users);
+		my %users = map { $_->user_id => 1 } @userVersions;
+		my @allUserRecords =
+			grep { $users{ $_->{user_id} } }
+			$c->db->getUsersWhere({ -and => { user_id => { not_like => 'set_id:%' } }, user_id => { '!=' => $userID } },
+				[qw/last_name first_name user_id/]);
 
 		if (@allUserRecords) {
 			my $filter = $c->param('studentNavFilter');
@@ -1390,13 +1394,15 @@ sub nav ($c, $args) {
 				# Add to the sections and recitations if defined.  Also store the first user found in that section or
 				# recitation.  This user will be switched to when the filter is selected.
 				my $section = $allUserRecords[$_]->section;
-				$filters{"section:$section"} =
-					[ $c->maketext('Filter by section [_1]', $section), $allUserRecords[$_]->user_id, $users[$_][2] ]
+				$filters{"section:$section"} = [
+					$c->maketext('Filter by section [_1]', $section), $allUserRecords[$_]->user_id,
+					$userVersions[$_][2]
+					]
 					if $section && !$filters{"section:$section"};
 				my $recitation = $allUserRecords[$_]->recitation;
 				$filters{"recitation:$recitation"} = [
 					$c->maketext('Filter by recitation [_1]', $recitation), $allUserRecords[$_]->user_id,
-					$users[$_][2]
+					$userVersions[$_][2]
 					]
 					if $recitation && !$filters{"recitation:$recitation"};
 
@@ -1413,7 +1419,7 @@ sub nav ($c, $args) {
 					($addRecord->last_name || $addRecord->first_name
 						? $addRecord->last_name . ', ' . $addRecord->first_name
 						: $addRecord->user_id);
-				$addRecord->{setVersion} = $users[$_][2];
+				$addRecord->{setVersion} = $userVersions[$_][2];
 			}
 
 			# Sort by last name, then first name, then user_id, then set version.

lib/WeBWorK/HTML/StudentNav.pm

@@ -15,13 +15,11 @@ sub studentNav ($c, $setID) {
 	return '' unless $c->authz->hasPermissions($userID, 'become_student');
 
 	# Find all users for the given set (except the current user) sorted by last_name, then first_name, then user_id.
-	my @allUserRecords = $c->db->getUsersWhere(
-		{
-			user_id =>
-				[ map { $_->[0] } $c->db->listUserSetsWhere({ set_id => $setID, user_id => { '!=' => $userID } }) ]
-		},
-		[qw/last_name first_name user_id/]
-	);
+	my %users = map { $_->[0] => 1 } $c->db->listUserSetsWhere({ set_id => $setID, user_id => { '!=' => $userID } });
+	my @allUserRecords =
+		grep { $users{ $_->{user_id} } }
+		$c->db->getUsersWhere({ -and => { user_id => { not_like => 'set_id:%' } }, user_id => { '!=' => $userID } },
+			[qw/last_name first_name user_id/]);
 
 	return '' unless @allUserRecords;
 
@@ -50,15 +48,11 @@ sub studentNav ($c, $setID) {
 			|| ($filter =~ /^section:(.*)$/    && $_->section eq $1)
 			|| ($filter =~ /^recitation:(.*)$/ && $_->recitation eq $1);
 
-		my $addRecord = $_;
-		$currentUserIndex = @userRecords if $addRecord->user_id eq $eUserID;
-		push @userRecords, $addRecord;
+		$currentUserIndex = @userRecords if $_->user_id eq $eUserID;
+		push @userRecords, $_;
 
 		# Construct a display name.
-		$addRecord->{displayName} =
-			($addRecord->last_name || $addRecord->first_name
-				? $addRecord->last_name . ', ' . $addRecord->first_name
-				: $addRecord->user_id);
+		$_->{displayName} = ($_->last_name || $_->first_name ? $_->last_name . ', ' . $_->first_name : $_->user_id);
 	}
 	my $prevUser = $currentUserIndex > 0             ? $userRecords[ $currentUserIndex - 1 ] : 0;
 	my $nextUser = $currentUserIndex < $#userRecords ? $userRecords[ $currentUserIndex + 1 ] : 0;