exclude subquery executed twice

[handrews]

When excluding using a subquery, I'm seeing the subquery being

executed first as its own query, then seeing the correct query being
run, including the subquery. Using filter instead of exclude, this
does not happen.

Here's what I mean (Select fields edited out of the MySQL log for
readability- connection 374 is from the Python prompt, 332 is me
poking at the mysql command line in another window to make sure I
don't confuse which queries go with which python statements). Version
and platform info follows:

>>> baz=Publisher.objects.all() 
>>> for s in Series.objects.filter(publisher__in=baz): 

...   pass 
... 
>>> for s in Series.objects.exclude(publisher__in=baz): 

...   pass 
... 

090509 19:30:22     332 Query       select count(*) from core_issue 
090509 19:30:28     374 Query       SELECT * FROM `core_series` WHERE `core_series`.`publisher_id` IN (SELECT U0.`id` FROM `core_publisher` U0) ORDER BY `core_series`.`name` ASC, `core_series`.`year_began` ASC 
090509 19:30:41     332 Query       select count(*) from core_issue 
090509 19:30:54     374 Query       SELECT * FROM `core_publisher` ORDER BY `core_publisher`.`name` ASC 
090509 19:30:55     374 Query       SELECT * FROM `core_series` WHERE NOT (`core_series`.`publisher_id` IN (SELECT U0.`id` FROM `core_publisher` U0)) ORDER BY `core_series`.`name` ASC, `core_series`.`year_began` ASC 

Version stuff:
Django 1.1 beta 1
Mac OS X 10.4.11
MySQL 5.0.45
Python 2.4.4
MySQLdb 1.2.1_p2

I checked on django-users first, where Alex Gaynor suggested that the issue is here:
​http://code.djangoproject.com/browser/django/trunk/django/db/models/sql/query.py#L1622

[Henry Andrews <hha1@…>]

Forgot to include the rest of Alex's comment about the code link "with the if not value triggering the issue. It's probably solvable by
changing that to if (not hasattr(value, 'as_sql') and not hasattr(value,
'_as_sql') and not value), but I haven't spent a ton of time thinking about
it."

Also, Malcolm Tredinnick replied that he could reproduce this.

[Alex Gaynor]

Fixed the formatting.