id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
8634	Wrong ordering by a field in a different table example in new (development ) queryset-api documentation	Jerzy.Ludwichowski@…	Ramiro Morales	"The example on ordering a queryset by a field in a different table in the  '''development''' documentation on queryset-api ([http://docs.djangoproject.com/en/dev/ref/models/querysets/#queryset-api]) offers the following syntax:


{{{
Entry.objects.order_by('blogs_blog.name', 'headline')
}}}

preceded by the following explanation: ""To order by a field in a different table, add the other table’s name and a dot, like so:""

For the following model definitions 

{{{
from django.db import models

class Poll(models.Model):
    question = models.CharField(max_length=200)
    pub_date = models.DateTimeField('date published')
    
    def __unicode__(self):
        return self.question


class Choice(models.Model):
    poll = models.ForeignKey(Poll)
    choices = models.CharField(max_length=200)
    votes = models.IntegerField()
    
    def __unicode__(self):
        return self.choices
}}}
 

with MySQL, for this retrieval example:


{{{
c=Choice.objects.order_by(""polls_poll.question"",'-votes')
list(c)
}}}

the result is ""OperationalError: (1054, ""Unknown column 'polls_poll.question' in 'order clause'"" in reply to the following SQL query generated:

{{{
SELECT `polls_choice`.`id`, `polls_choice`.`poll_id`, `polls_choice`.`choices`,
`polls_choice`.`votes` FROM `polls_choice` ORDER BY `polls_poll`.question ASC,
 `polls_choice`.`votes` DESC
}}}

On the other hand 
if one follows the syntax offered in the ""mainstream"" documentation (http://www.djandoproject.com/db-api), i.e.,  

{{{
c=Choice.objects.order_by(""poll__question"",'-votes')
list(c) 
}}}

things do work, with the following SQL query generated:


{{{
SELECT `polls_choice`.`id`, `polls_choice`.`poll_id`, `polls_choice`.`choices`,
`polls_choice`.`votes` FROM `polls_choice` INNER JOIN `polls_poll` 
ON (`polls_choice`.`poll_id` = `polls_poll`.`id`) ORDER BY `polls_poll`.`question` ASC, 
`polls_choice`.`votes` DESC

}}}

This problem might be related to the one reported in the accepted ticket #2884 (component: Admin interface), solution for which is said to be deferred until after queryset-refactor. "		closed	Documentation	dev		fixed			Accepted	1	0	0	0	0	0