Refs #2495 -- Documented that MySQL cannot have TextField(unique=True).

This commit is contained in:
Tim Graham 2015-08-27 09:29:13 -04:00
parent 7bec480fe2
commit e8cbc2b322
1 changed files with 8 additions and 0 deletions

View File

@ -513,6 +513,14 @@ for the field. This affects :class:`~django.db.models.CharField`,
:class:`~django.db.models.SlugField` and
:class:`~django.db.models.CommaSeparatedIntegerField`.
``TextField`` limitations
~~~~~~~~~~~~~~~~~~~~~~~~~
MySQL can index only the first N chars of a ``BLOB`` or ``TEXT`` column. Since
``TextField`` doesn't have a defined length, you can't mark it as
``unique=True``. MySQL will report: "BLOB/TEXT column '<db_column>' used in key
specification without a key length".
.. _mysql-fractional-seconds:
Fractional seconds support for Time and DateTime fields