Clarify documentation on Field.blank and Field.null options

[skipjack@…]

I find the documentation on the 'null' and 'blank' options for model fields do miss one point.

It is clearly stated that 'null' is for the database contraints and 'blank' is for the form validation (less clear though). While there are almost two paragraphs describing the correct setting for allowing empty string values (null=False, blank=True), it is not perfectly clear what setting is needed in order to deal with empty values for the remaining field types.

I missed one sentence like for (almost?) all other field types you need to set both blank and null to True in order to allow for empty values in your model.

Or am I missing something else? (I'm quite new to Django.)

For reference:

• ​https://docs.djangoproject.com/en/dev/ref/models/fields/#null
• ​https://docs.djangoproject.com/en/dev/ref/models/fields/#blank

[Daniele Procida]

I agree that this could be improved. There's the additional issue in that we say:

Only use null=True for non-string fields

followed by:

Avoid using null on string-based fields such as CharField and TextField unless you have an excellent reason.

which repeats itself, but in an inconsistent way!

[out0fbound]

Clarify documentation on Field.blank and Field.null options

[out0fbound]

Added patch 22145.patch and created a pull request for this ticket(​https://github.com/django/django/pull/2367)

[Tim Graham <timograham@…>]

In 3390550f6f645f82354eaffa1d3c89dfa041f1aa:

Fixed #22145 -- Clarified docs on Field.blank and Field.null options.

Thanks skipjack at peru.com for the suggestion.

[Tim Graham <timograham@…>]

In f2b513c9e8416855a92e66928c2e22a8fc639273:

[1.6.x] Fixed #22145 -- Clarified docs on Field.blank and Field.null options.

Thanks skipjack at peru.com for the suggestion.

Backport of 3390550f6f from master