Updating the primary key skylar diggins dating daniel
This may be desirable if you want to update just one or a few fields on an object.
There will be a slight performance benefit from preventing all of the model fields from being updated in the database. This only deletes the object in the database; the Python instance will still exist and will still have data in its fields.
The example below shows how one can reload all of the instance’s fields when a deferred field is reloaded: This method should be used to provide custom model validation, and to modify attributes on your model if desired.
For instance, you could use it to automatically provide a value for a field, or to do validation that requires access to more than a single field: .
If you generate a pickle using Django version N, there is no guarantee that pickle will be readable with Django version N 1.
Pickles should not be used as part of a long-term archival strategy.
For more on this nuance, see Explicitly specifying auto-primary-key values above and Forcing an INSERT or UPDATE below.
In Django 1.5 and earlier, Django did a update at the same time!
You can read and set this value, just as you would for any other attribute, and it will update the correct field in the model.However, if the "IF NOT EXISTS" clause is specified as part of the CREATE TABLE statement and a table or view of the same name already exists, the CREATE TABLE command simply has no effect (and no error message is returned).