[1.2.X] Fixed #14700 -- ensure that a raw query is only executed once per...

[1.2.X] Fixed #14700 -- ensure that a raw query is only executed once per iteration.  Backport of [14785].

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@14786 bcc190cf-cafb-0310-a4f2-bffc1f526a37