diff --git a/db.py b/db.py
index 93c9c24..9c31114 100755
--- a/db.py
+++ b/db.py
@@ -8,7 +8,7 @@ from sqlalchemy.orm import scoped_session, sessionmaker, relationship, backref
 from sqlalchemy.ext.declarative import declarative_base
 
 from sqlalchemy.types import TypeDecorator
-from sqlalchemy import BINARY
+from sqlalchemy.types import BINARY
 
 import uuid, datetime
 import os.path
@@ -39,6 +39,9 @@ class UUID(TypeDecorator):
 	def gen_id_column():
 		return Column(UUID, primary_key = True, default = uuid.uuid4)
 
+def now():
+	return datetime.datetime.now().replace(microsecond = 0)
+
 engine = create_engine(config.get('DATABASE_URI'), convert_unicode = True)
 session = scoped_session(sessionmaker(autocommit = False, autoflush = False, bind = engine))
 
@@ -64,6 +67,7 @@ class Folder(Base):
 	root = Column(Boolean, default = False)
 	name = Column(String)
 	path = Column(String, unique = True)
+	created = Column(DateTime, default = now)
 	has_cover_art = Column(Boolean, default = False)
 	last_scan = Column(DateTime, default = datetime.datetime.min)
 
@@ -75,6 +79,7 @@ class Folder(Base):
 			'id': str(self.id),
 			'isDir': True,
 			'title': self.name,
+			'created': self.created.isoformat()
 		}
 		if not self.root:
 			info['parent'] = str(self.parent_id)
@@ -110,9 +115,12 @@ class Track(Base):
 	genre = Column(String, nullable = True)
 	duration = Column(Integer)
 	album_id = Column(UUID, ForeignKey('album.id'))
-	path = Column(String, unique = True)
 	bitrate = Column(Integer)
 
+	path = Column(String, unique = True)
+	created = Column(DateTime, default = now)
+	last_modification = Column(Integer)
+
 	root_folder_id = Column(UUID, ForeignKey('folder.id'))
 	root_folder = relationship('Folder', primaryjoin = Folder.id == root_folder_id)
 	folder_id = Column(UUID, ForeignKey('folder.id'))
@@ -135,6 +143,7 @@ class Track(Base):
 			'path': self.path[len(self.root_folder.path) + 1:],
 			'isVideo': False,
 			'discNumber': self.disc,
+			'created': self.created.isoformat(),
 			'albumId': str(self.album.id),
 			'artistId': str(self.album.artist.id),
 			'type': 'music'
@@ -151,7 +160,6 @@ class Track(Base):
 		# transcodedSuffix
 		# userRating
 		# averageRating
-		# created
 		# starred
 
 		return info
diff --git a/scanner.py b/scanner.py
index cfd9893..cf2fb17 100755
--- a/scanner.py
+++ b/scanner.py
@@ -9,15 +9,16 @@ import db
 class Scanner:
 	def __init__(self, session):
 		self.__session = session
+		self.__tracks  = db.Track.query.all()
 		self.__artists = db.Artist.query.all()
 		self.__folders = db.Folder.query.all()
 
 		self.__added_artists = 0
-		self.__added_albums = 0
-		self.__added_tracks = 0
+		self.__added_albums  = 0
+		self.__added_tracks  = 0
 		self.__deleted_artists = 0
-		self.__deleted_albums = 0
-		self.__deleted_tracks = 0
+		self.__deleted_albums  = 0
+		self.__deleted_tracks  = 0
 
 	def scan(self, folder):
 		for root, subfolders, files in os.walk(folder.path):
@@ -27,21 +28,20 @@ class Scanner:
 		folder.last_scan = datetime.datetime.now()
 
 	def prune(self, folder):
-		for artist in db.Artist.query.all():
-			for album in artist.albums[:]:
-				for track in filter(lambda t: t.root_folder.id == folder.id, album.tracks):
-					if not os.path.exists(track.path):
-						album.tracks.remove(track)
-						track.folder.tracks.remove(track)
-						self.__session.delete(track)
-						self.__deleted_tracks += 1
-				if len(album.tracks) == 0:
-					artist.albums.remove(album)
-					self.__session.delete(album)
-					self.__deleted_albums += 1
-			if len(artist.albums) == 0:
-				self.__session.delete(artist)
-				self.__deleted_artists += 1
+		for track in [ t for t in self.__tracks if t.root_folder.id == folder.id and not os.path.exists(t.path) ]:
+			track.album.tracks.remove(track)
+			track.folder.tracks.remove(track)
+			self.__session.delete(track)
+			self.__deleted_tracks += 1
+
+		for album in [ album for artist in self.__artists for album in artist.albums if len(album.tracks) == 0 ]:
+			album.artist.albums.remove(album)
+			self.__session.delete(album)
+			self.__deleted_albums += 1
+
+		for artist in [ a for a in self.__artists if len(a.albums) == 0 ]:
+			self.__session.delete(artist)
+			self.__deleted_artists += 1
 
 		self.__cleanup_folder(folder)
 
@@ -51,17 +51,19 @@ class Scanner:
 			self.check_cover_art(f)
 
 	def __scan_file(self, path, folder):
-		tag = eyeD3.Tag()
-		tag.link(path)
-		audio_file = eyeD3.Mp3AudioFile(path)
-
-		al = self.__find_album(tag.getArtist(), tag.getAlbum())
-		tr = filter(lambda t: t.path == path, al.tracks)
+		tr = filter(lambda t: t.path == path, self.__tracks)
 		if not tr:
 			tr = db.Track(path = path, root_folder = folder, folder = self.__find_folder(path, folder))
+			self.__tracks.append(tr)
 			self.__added_tracks += 1
 		else:
 			tr = tr[0]
+			if not os.path.getmtime(path) > tr.last_modification:
+				return
+
+		tag = eyeD3.Tag()
+		tag.link(path)
+		audio_file = eyeD3.Mp3AudioFile(path)
 
 		tr.disc = tag.getDiscNum()[0] or 1
 		tr.number = tag.getTrackNum()[0] or 1
@@ -69,8 +71,9 @@ class Scanner:
 		tr.year = tag.getYear()
 		tr.genre = tag.getGenre().name if tag.getGenre() else None
 		tr.duration = audio_file.getPlayTime()
-		tr.album = al
+		tr.album = self.__find_album(tag.getArtist(), tag.getAlbum())
 		tr.bitrate = audio_file.getBitRate()[1]
+		tr.last_modification = os.path.getmtime(path)
 
 	def __find_album(self, artist, album):
 		ar = self.__find_artist(artist)