just in case commit to prevent join string iteration over 'None' values

plugins/dbms/mssqlserver/enumeration.py

@@ -77,6 +77,8 @@ class Enumeration(GenericEnumeration):
         for db in dbs:
             dbs[dbs.index(db)] = safeSQLIdentificatorNaming(db)
 
+        dbs = filter(None, dbs)
+
         infoMsg = "fetching tables for database"
         infoMsg += "%s: %s" % ("s" if len(dbs) > 1 else "", ", ".join(db for db in sorted(dbs)))
         logger.info(infoMsg)