diff --git a/rhodecode/__init__.py b/rhodecode/__init__.py
--- a/rhodecode/__init__.py
+++ b/rhodecode/__init__.py
@@ -51,7 +51,7 @@ except ImportError:
 
 __version__ = ('.'.join((str(each) for each in VERSION[:3])) +
                '.'.join(VERSION[3:]))
-__dbversion__ = 13  # defines current db version for migrations
+__dbversion__ = 14  # defines current db version for migrations
 __platform__ = platform.system()
 __license__ = 'GPLv3'
 __py_version__ = sys.version_info
diff --git a/rhodecode/lib/db_manage.py b/rhodecode/lib/db_manage.py
--- a/rhodecode/lib/db_manage.py
+++ b/rhodecode/lib/db_manage.py
@@ -30,6 +30,7 @@ import time
 import uuid
 import logging
 from os.path import dirname as dn, join as jn
+import datetime
 
 from rhodecode import __dbversion__, __py_version__
 
@@ -216,6 +217,13 @@ class UpgradeSteps(object):
     def step_13(self):
         pass
 
+    def step_14(self):
+        # fix nullable columns on last_update
+        for r in RepoModel().get_all():
+            if r.updated_on is None:
+                r.updated_on = datetime.datetime.fromtimestamp(0)
+                Session().add(r)
+        Session().commit()
 
 class DbManage(object):
     def __init__(self, log_sql, dbconf, root, tests=False, cli_args={}):
diff --git a/rhodecode/lib/dbmigrate/versions/014_version_1_7_1.py b/rhodecode/lib/dbmigrate/versions/014_version_1_7_1.py
new file mode 100644
--- /dev/null
+++ b/rhodecode/lib/dbmigrate/versions/014_version_1_7_1.py
@@ -0,0 +1,38 @@
+import logging
+import datetime
+
+from sqlalchemy import *
+from sqlalchemy.exc import DatabaseError
+from sqlalchemy.orm import relation, backref, class_mapper, joinedload
+from sqlalchemy.orm.session import Session
+from sqlalchemy.ext.declarative import declarative_base
+
+from rhodecode.lib.dbmigrate.migrate import *
+from rhodecode.lib.dbmigrate.migrate.changeset import *
+
+from rhodecode.model.meta import Base
+from rhodecode.model import meta
+from rhodecode.lib.dbmigrate.versions import _reset_base
+
+log = logging.getLogger(__name__)
+
+
+def upgrade(migrate_engine):
+    """
+    Upgrade operations go here.
+    Don't create your own engine; bind migrate_engine to your metadata
+    """
+    _reset_base(migrate_engine)
+
+    #==========================================================================
+    # Gist
+    #==========================================================================
+    from rhodecode.lib.dbmigrate.schema.db_1_7_0 import Gist
+    tbl = Gist.__table__
+    user_id = tbl.columns.gist_expires
+    user_id.alter(type=Float(53))
+
+
+def downgrade(migrate_engine):
+    meta = MetaData()
+    meta.bind = migrate_engine