diff --git a/db_schema.sql b/db_schema.sql
index c66eb86892ed3a4fb963ed0d2299965bf0e16b22..f85b8c52f9fbf3a01d526c64c5b2c6707beaafd3 100644
--- a/db_schema.sql
+++ b/db_schema.sql
@@ -128,6 +128,7 @@ CREATE TABLE IF NOT EXISTS `log` (
 	`ip` varchar(64),
 	`id` varchar(64),
 	`time` datetime NOT NULL,
+	`source` varchar(8),
 	`object` varchar(10),
 	`obj_id` INTEGER,
 	`path` varchar(255) NOT NULL
diff --git a/server.py b/server.py
index 50069ccfaebd9574f78087ad9de1c39266eb9a78..fbf3b724d341d88ac86fcef35a7f5e23fc88c38b 100644
--- a/server.py
+++ b/server.py
@@ -323,7 +323,7 @@ def courses():
 		if course['semester'] == '':
 			course['semester'] = 'zeitlos'
 	groupedby = request.args.get('groupedby')
-	if groupedby not in ['title', 'semester', 'organizer']:
+	if groupedby not in ['title', 'semester', 'organizer', 'subject']:
 		groupedby = 'semester'
 	return render_template('courses.html', courses=courses, groupedby=groupedby)
 
@@ -552,7 +552,7 @@ def auth(): # For use with nginx auth_request
 		password = auth.password
 	if checkperm(perms, username=username, password=password):
 		try:
-			modify('INSERT INTO log VALUES (?, ?, ?, "video", ?, ?)', ip, cookie, datetime.now(), perms[0]['vid'], url)
+			modify('INSERT INTO log (ip, id, `time`, object, obj_id, path) VALUES (?, ?, ?, "video", ?, ?)', ip, cookie, datetime.now(), perms[0]['vid'], url)
 		except:
 			pass
 		r = make_response('OK', 200)
diff --git a/stats.py b/stats.py
index 347bc71cc2f0edc5d6fe4c149c9d2c5ea79e8a7a..0f188af9913643766a633ff0e7708d0f1d92ead9 100644
--- a/stats.py
+++ b/stats.py
@@ -29,7 +29,10 @@ def stats_generic(req, param=None):
 	rows = query(statsqueries[req], *(statsqueries[req].count('?')*[param]))
 	res = {'x':[], 'y':[]}
 	for row in rows:
-		res['x'].append(row['x'])
+		if row['x'] != '':
+			res['x'].append(row['x'])
+		else:
+			res['x'].append('leer')
 		res['y'].append(row['y'])
 	return Response(json.dumps(res, default=plotly_date_handler),  mimetype='application/json')
 
diff --git a/templates/courses.html b/templates/courses.html
index 1d0313e4179077a60a9dc0bcd8accc77cd6fd980..9c8ff488b527cdbfa9132c39122d10b6b27ac93d 100644
--- a/templates/courses.html
+++ b/templates/courses.html
@@ -19,8 +19,9 @@
 				</button>
 				<ul class="dropdown-menu dropdown-menu-right">
 					<li><a href="?groupedby=semester">Semester</a></li>
-					<li><a href="?groupedby=title">Veranstaltungen</a></li>
-					<li><a href="?groupedby=organizer">Dozenten</a></li>
+					<li><a href="?groupedby=title">Veranstaltung</a></li>
+					<li><a href="?groupedby=organizer">Dozent</a></li>
+					<li><a href="?groupedby=subject">Kategorie</a></li>
 				</ul>
 			</li>
 		</ul>