upgrading database (sqlite:///state.sqlite)
Traceback (most recent call last):
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/internet/defer.py", line 391, in errback
    self._startRunCallbacks(fail)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/internet/defer.py", line 458, in _startRunCallbacks
    self._runCallbacks()
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/internet/defer.py", line 545, in _runCallbacks
    current.result = callback(current.result, *args, **kw)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/internet/defer.py", line 910, in gotResult
    _deferGenerator(g, deferred)
--- <exception caught here> ---
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/internet/defer.py", line 885, in _deferGenerator
    result = g.next()
  File "/home/deegan/dev/bb_git/buildbot/master/buildbot/scripts/runner.py", line 434, in upgradeMaster
    wfd.getResult()
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/internet/defer.py", line 864, in getResult
    self.result.raiseException()
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/python/threadpool.py", line 207, in _worker
    result = context.call(ctx, function, *args, **kwargs)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/python/context.py", line 118, in callWithContext
    return self.currentContext().callWithContext(ctx, func, *args, **kw)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/twisted/python/context.py", line 81, in callWithContext
    return func(*args,**kw)
  File "/home/deegan/dev/bb_git/buildbot/master/buildbot/db/pool.py", line 177, in __thd
    rv = callable(arg, *args, **kwargs)
  File "/home/deegan/dev/bb_git/buildbot/master/buildbot/db/model.py", line 472, in thd
    upgrade(engine)
  File "/home/deegan/dev/bb_git/buildbot/master/buildbot/db/model.py", line 442, in upgrade
    schema.runchange(version, change, 1)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/migrate/versioning/schema.py", line 91, in runchange
    change.run(self.engine, step)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/migrate/versioning/script/py.py", line 145, in run
    script_func(engine)
  File "/home/deegan/dev/bb_git/buildbot/master/buildbot/db/migrate/versions/018_add_sourcestampset.py", line 45, in upgrade
    buildsets_table = sa.Table('buildsets', metadata, autoload=True)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/schema.py", line 303, in __new__
    table._init(name, metadata, *args, **kw)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/schema.py", line 366, in _init
    self._autoload(metadata, autoload_with, include_columns)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/schema.py", line 390, in _autoload
    self, include_columns, exclude_columns
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 2276, in run_callable
    return conn.run_callable(callable_, *args, **kwargs)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1900, in run_callable
    return callable_(self, *args, **kwargs)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/engine/default.py", line 259, in reflecttable
    return insp.reflecttable(table, include_columns, exclude_columns)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/engine/reflection.py", line 394, in reflecttable
    sql.text(col_d['default']), _reflected=True
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/sql/expression.py", line 1129, in text
    return _TextClause(text, bind=bind, *args, **kwargs)
  File "/home/deegan/dev/bb_git/sandbox/lib/python2.7/site-packages/sqlalchemy/sql/expression.py", line 2842, in __init__
    self.text = self._bind_params_regex.sub(repl, text)
exceptions.TypeError: expected string or buffer