Q objects --- sku data acquisition

Q objects

versus

or

Example: Query reading greater than 20 books, rewrite Q objects as follows.

from django.db.models import Q

BookInfo.objects.filter(Q(bread__gt=20))

• Q & objects may be used and | connected, & presentation logic, | represents logical OR.

Example: Read Query greater than 20, or less than the number of books 3, use only Q object implementation

BookInfo.objects.filter(Q(bread__gt=20) | Q(pk__lt=3))

non-

Q ~ operator using objects before, represents a non-not.

Example: the query number is not equal to 3 books.

BookInfo.objects.filter(~Q(pk=3))