Comment 0 for bug 825809

Hello,

trunk r1708, archlinux

1) Go to "Tools -> Song Usage Tracking -> Extract Tracking Data"
2) Choose a directory to save the report
3) Try to extract the report.

 --- Exception Traceback ---
Traceback (most recent call last):
  File "/home/andreas/Projekte/openlp/trunk/openlp/plugins/songusage/forms/songusagedetailform.py", line 114, in accept
    [SongUsageItem.usagedate, SongUsageItem.usagetime])
  File "/home/andreas/Projekte/openlp/trunk/openlp/core/lib/db.py", line 227, in get_all_objects
    return query.order_by(order_by_ref).all()
  File "<string>", line 1, in <lambda>
  File "/usr/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 50, in generate
    fn(self, *args[1:], **kw)
  File "/usr/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 1054, in order_by
    criterion = self._adapt_col_list(criterion)
  File "/usr/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 205, in _adapt_col_list
    for o in cols
  File "/usr/lib/python2.7/site-packages/sqlalchemy/sql/expression.py", line 1279, in _literal_as_text
    "SQL expression object or string expected."
ArgumentError: SQL expression object or string expected.

--- Library Versions ---
Python: 2.7.2
Qt4: 4.7.3
Phonon: 4.5.55
PyQt4: 4.8.5
SQLAlchemy: 0.7.1
BeautifulSoup: 3.2.0
lxml: 2.3.0
Chardet: 2.0.1
PyEnchant: 1.6.3
PySQLite: -