[repo, hooks] small task optimization: don't start cleanup_old_transactions when undo support is not activated, and retrieve a session to update a source only when some source to update is found
sync_schema_props_perms('CWSourceHostConfig', syncperms=False)
sql('INSERT INTO cw_source_relation(eid_from, eid_to) '
'SELECT e.eid,s.cw_eid FROM entities as e, cw_CWSource as s '
'WHERE s.cw_name=e.source AND NOT EXISTS(SELECT 1 FROM cw_source_relation WHERE eid_from=e.eid AND eid_to=s.cw_eid)')
commit()