How to show database in django-admin using filters by default?

Question

I need to filter database by default every time that I see it (when I save changes or when I open database first time). Can anybody tell me how to do it?

Answer 1

This is possible with custom custom Managers:

Say you have a class called Book:

class Book(models.Model):
    title = models.CharField(max_length=100)
    author = models.CharField(max_length=50)

And you want the admin pages for book objects to only show books by Roald Dahl, then you can add a custom manager:

class DahlBookManager(models.Manager):
    def get_query_set(self):
        return super(DahlBookManager, self).get_query_set().filter(author='Roald Dahl')

class Book(models.Model):
    title = models.CharField(max_length=100)
    author = models.CharField(max_length=50)

    objects = models.Manager()
    dahl_objects = DahlBookManager()

Then you just need to specify that your ModelAdmin should use the dahl_objects manager, which is explained here.

Answer 2

here is my modes.py:

from django.db import models

class DahlBookManager(models.Manager):
    def get_query_set(self):
    return super(DahlBookManager, self).get_query_set().filter(processed=False)

class Book(models.Model):
    book_name = models.CharField('book',max_length=1000,null=True, blank=True)
    url = models.CharField(max_length=1000,null=True, blank=True)
    processed = models.BooleanField('Done',)

    def __str__(self):
        return u'%s' % (self.book_name)

    def url1(self):
    return '<a href="%s">%s</a>' % (self._url, self.url)
    site_url1.allow_tags = True

    class Admin:
    pass

    class Meta:
        db_table = 'books'

    objects = models.Manager()
    dahl_objects = DahlBookManager()

here is my admin.py:

from django.contrib import admin
from mybooks.booksdb.models import Book
from django import forms

admin.autodiscover()

class BookAdmin(admin.ModelAdmin):
    def queryset(self,request):
        qs=self.model.objects.get_query_set()
        ordering = self.ordering or ()      
        if ordering:
            qs=qs.order_by(*ordering)
        return qs
....

No filter by default. Where is my miss?