fix Traceback like Jonathan recommand

openlp/core/lib/db.py

@@ -34,6 +34,7 @@ from PyQt4 import QtCore
 from sqlalchemy import create_engine, MetaData
 from sqlalchemy.exceptions import InvalidRequestError
 from sqlalchemy.orm import scoped_session, sessionmaker
+from sqlalchemy.pool import NullPool
 
 from openlp.core.utils import AppLocation, delete_file
 
@@ -52,7 +53,7 @@ def init_db(url, auto_flush=True, auto_commit=False):
     ``auto_commit``
         Sets the commit behaviour of the session
     """
-    engine = create_engine(url)
+    engine = create_engine(url, poolclass=NullPool)
     metadata = MetaData(bind=engine)
     session = scoped_session(sessionmaker(autoflush=auto_flush,
         autocommit=auto_commit, bind=engine))

openlp/plugins/bibles/lib/db.py

@@ -500,12 +500,6 @@ class BibleDB(QtCore.QObject, Manager):
             return True
         return False
 
-    def close_database(self):
-        """
-        Close database connection.
-        """
-        self.session.close()
-
     def dump_bible(self):
         """
         Utility debugging method to dump the contents of a bible.
@@ -1006,13 +1000,6 @@ class OldBibleDB(QtCore.QObject, Manager):
             self.cursor = conn.cursor()
         return self.cursor
 
-    def close_cursor(self):
-        """
-        Close the cursor
-        """
-        if self.cursor:
-            self.cursor.close()
-
     def run_sql(self, query, parameters=()):
         """
         Run an SQL query on the database, returning the results.

openlp/plugins/bibles/lib/manager.py

@@ -156,6 +156,7 @@ class BibleManager(object):
             # Find old database versions
             if bible.is_old_database():
                 self.old_bible_databases.append(filename)
+                bible.session.close()
                 continue
             log.debug(u'Bible Name: "%s"', name)
             self.db_cache[name] = bible