From 24d53786d414586bb56243758cec41e802e8947d Mon Sep 17 00:00:00 2001 From: Paolo Melchiorre Date: Mon, 27 Mar 2017 20:07:11 +0200 Subject: [PATCH] Made a few cosmetic updates to "Migrations that add unique fields". --- docs/howto/writing-migrations.txt | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/docs/howto/writing-migrations.txt b/docs/howto/writing-migrations.txt index bd1968ccb8..55b30e9c98 100644 --- a/docs/howto/writing-migrations.txt +++ b/docs/howto/writing-migrations.txt @@ -94,8 +94,8 @@ the respective field according to your needs. give them meaningful names in the examples below. * Copy the ``AddField`` operation from the auto-generated migration (the first - of the three new files) to the last migration and change ``AddField`` to - ``AlterField``. For example: + of the three new files) to the last migration, change ``AddField`` to + ``AlterField``, and add imports of ``uuid`` and ``models``. For example: .. snippet:: :filename: 0006_remove_uuid_null.py @@ -104,7 +104,6 @@ the respective field according to your needs. from django.db import migrations, models import uuid - class Migration(migrations.Migration): dependencies = [ @@ -146,7 +145,8 @@ the respective field according to your needs. * In the first empty migration file, add a :class:`~django.db.migrations.operations.RunPython` or :class:`~django.db.migrations.operations.RunSQL` operation to generate a - unique value (UUID in the example) for each existing row. For example: + unique value (UUID in the example) for each existing row. Also add an import + of ``uuid``. For example: .. snippet:: :filename: 0005_populate_uuid_values.py @@ -159,7 +159,7 @@ the respective field according to your needs. MyModel = apps.get_model('myapp', 'MyModel') for row in MyModel.objects.all(): row.uuid = uuid.uuid4() - row.save() + row.save(update_fields=['uuid']) class Migration(migrations.Migration):