django - 如何从 Django View 中的模型访问数据？

Question

所以我有一个模型文件:

import datetime

from django.db import models

class Organization(models.Model):
    name           = models.CharField(max_length=128, unique=True);
    description    = models.TextField(blank=True);
    location       = models.CharField(max_length=256, blank=True);
    contact_email  = models.EmailField(max_length=128, unique=True);
    org_type       = models.ForeignKey('OrganizationType');
    created_at     = models.DateTimeField(editable=False);
    updated_at     = models.DateTimeField();

def save(self, *args, **kwargs):
    ''' On save, update timestamps '''
    datetime_now = datetime.datetime.now();

    # If there's no ID, it's new
    if not self.id:
        self.created_at = datetime_now;

    # Always update the modified at value
    self.modified_at = datetime_now;

    return super(User, self).save(*args, **kwargs);

class Meta:
    app_label = 'bc';

和一个 View 文件 Organization.py:

from django.shortcuts import render, redirect
from django.contrib import auth
from django.core.context_processors import csrf

from BearClubs.bc.forms.user import UserSignUpForm
from BearClubs.bc.models.organization import Organization

def directory(request):
    first_50_clubs = [];

    # get 50 clubs here

return render(request, 'directory.html' {'clubs': first_50_clubs});

我对 Django 真的很陌生，所以请原谅我。如何获取 Organization.py View 文件中 first_50_clubs 中的前 50 个俱乐部？

Answer 1

根据documentation ，你可以只使用列表切片:

Use a subset of Python’s array-slicing syntax to limit your QuerySet to a certain number of results. This is the equivalent of SQL’s LIMIT and OFFSET clauses.

def directory(request):
    first_50_clubs = Organization.objects.all()[:50]

    return render(request, 'directory.html' {'clubs': first_50_clubs})

此外，您不需要在 python 中的代码行末尾放置分号。

希望有帮助。