Dry ORM

Code

Result

no cache

from django.db import models
from django.db.models import F
from django.utils import timezone

class Entry(models.Model):
    title = models.CharField(max_length=100)
    created = models.DateTimeField(default=timezone.now)
    published = models.DateTimeField(null=True, blank=True)

def run():
    # Bootstrap sample data
    Entry.objects.all().delete()
    now = timezone.now()
    Entry.objects.create(title="Post A", created=now - timezone.timedelta(days=3))
    Entry.objects.create(title="Post B", created=now - timezone.timedelta(days=2))
    Entry.objects.create(title="Post C", created=now - timezone.timedelta(days=1), published=now)

print(f'Before update, unpublished count: {Entry.objects.filter(published__isnull=True).count()}')

# Single efficient bulk update: set published = created where published is NULL
    updated = Entry.objects.filter(published__isnull=True).update(published=F('created'))
    print(f'Rows updated: {updated}')

print('Entries after update (id, title, created, published):')
    for row in Entry.objects.all():
        print(row.title, row.created == row.published)

Output

No output.

Queries

Queries Q (0)

No queries.