Django admin list_display用外键奇怪的慢 [英] Django admin list_display weirdly slow with foreign keys

问题描述

Django 1.2.5
Python：2.5.5

Django 1.2.5 Python: 2.5.5

我的运动模型的管理列表刚刚走得很慢（400条记录5分钟） 。一秒钟内返回，直到我们有400场比赛，50支球队和2场运动。

My admin list of a sports model has just gone really slow (5 minutes for 400 records). It was returning in a second or so until we got 400 games, 50 odd teams and 2 sports.

我已经修复了一个糟糕的方式，所以我想看看有没有人看过这个。我的应用程序如下所示：

I have fixed it in an awful way so I'd like to see if anyone has seen this before. My app looks like this:

models:

Sport( models.Model )
    name

Venue( models.Model )
    name

Team( models.Model )
    name

Fixture( models.Model )
    date
    sport = models.ForeignKey(Sport)
    venue = models.ForeignKey(Venue)

TeamFixture( Fixture )
    team1 = models.ForeignKey(Team, related_name="Team 1")
    team2 = models.ForeignKey(Team, related_name="Team 2")


admin:

TeamFixture_ModelAdmin (ModelAdmin)
    list_display = ('date','sport','venue','team1','team2',)

如果我从list_display中删除任何外键，那么它很快。一旦我添加任何外键，然后缓慢。

If I remove any foreign keys from list_display then it's quick. As soon as I add any foreign key then slow.

我通过使用非外键来修复它，但是在模型init中计算它，所以这样工作：

I fixed it by using non foreign keys but calculating them in the model init so this works:

models:

TeamFixture( Fixture )
    team1 = models.ForeignKey(Team, related_name="Team 1")
    team2 = models.ForeignKey(Team, related_name="Team 2")
    sport_name = ""
    venue_name = ""
    team1_name = ""
    team2_name = ""

    def __init__(self, *args, **kwargs):
        super(TeamFixture, self).__init__(*args, **kwargs)

        self.sport_name = self.sport.name
        self.venue_name = self.venue.name
        self.team1_name = self.team1.name
        self.team2_name = self.team2.name

admin:

TeamFixture_ModelAdmin (ModelAdmin)
    list_display = ('date','sport_name','venue_name','team1_name','team2_name',)

所有其他型号的管理现在几千条记录是正常的，实际网站中的所有视图都正常运行。

Administration for all other models are fine with several thousand records at the moment and all views in the actual site is functioning fine.

推荐答案

这让我很疯狂。 list_select_related设置为True，但是在list_display中向User添加外键会在admin中为每行生成一个查询，这使得列表缓慢。 Select_related为True，所以Django管理员不应该在每行上调用此查询。
发生了什么？

It's driving me crazy. list_select_related is set to True, however adding a foreign key to User in the list_display generates one query per row in the admin, which makes the listing slow. Select_related is True, so the Django admin shouldn't call this query on each row. What is going on ?

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