Question

您是否知道如何优化（时间）此查询？即使wordpress人口大约是1000，它也是如此。

查询：

al = Wordpress.objects.all().order_by('?')
zaplecza = Wordpress.objects.none()
for l in labels.split(","):
    zaplecza = zaplecza | al.filter(label = l)    
zaplecza = zaplecza.exclude(wordpress__url = project_name) <--very slow

models.py

class Wordpress(models.Model):
    url = models.CharField(max_length = 1000)
    login = models.CharField(max_length = 1000, default = "admin")
    password = models.CharField(max_length = 1000, default = "perkoz")
    label = models.CharField(max_length = 1000)
    cms = models.CharField(max_length = 1000)


class Project(models.Model):
    url = models.CharField(max_length = 1000)
    links = models.TextField(blank = True, null = True, verbose_name = "Linki do wpisów")
    wordpress = models.ManyToManyField(Wordpress, related_name = "wordpress", verbose_name = "Dodane do zaplecz")

    main_link = models.CharField(max_length = 1000)
    dir_links = models.TextField(blank = True, null = True, verbose_name="Anchory")
    blog_links = models.TextField(blank = True, null = True, verbose_name="Lista linków i anchorów z ;;;")
    category = models.ForeignKey(Category, related_name = "projekt")
    kategorie = models.CharField(max_length = 1000)
    labels = models.CharField(max_length = 1000)
    tagi = models.CharField(max_length = 1000)
    auto_tekst = models.BooleanField(verbose_name="Auto tekst")
    arts = models.TextField(blank = True, null = True, verbose_name="Artykuły")
    title = models.TextField(blank = True, null = True, verbose_name="Tytuł")
    no = models.IntegerField(blank = True, null = True, verbose_name="Liczba wpisów")
    last_added = models.DateTimeField(blank = True, null = True, verbose_name="Ostatnio dodane")

Answer 1

您正在获取m2m相关对象，因此您应该在查询中使用prefetch_related来优化它。

https://docs.djangoproject.com/en/dev/ref/models/querysets/#django.db.models.query.QuerySet.prefetch_related

Django多对多的过滤优化

1 个答案: