id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
25626	Storing big strings with special chars fails when using PostgreSQL with SQL_ASCII encoding	JoseTomasTocino	nobody	"If a project uses a PostgreSQL database with SQL_ASCII encoding, a model with a CharField may raise a {{{DataError: value too long}}} error when storing strings with special characters.

Supposing a simple model like this:

{{{
#!python
class TestModel(models.Model):
    title = models.CharField(max_length=5)
}}}

And a PostgreSQL database called `testing` with SQL_ASCII encoding, that can be created using:
{{{
#!sql
CREATE DATABASE testing WITH TEMPLATE = template0 ENCODING = 'SQL_ASCII';
}}}

If you try to add an instance of the model with a title with special characters it fails, even being under the length limit:

{{{
#!python
TestModel.objects.create(title=""ñññ"")
}}}

{{{
#!pytb
Traceback (most recent call last):
  File ""<console>"", line 1, in <module>
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/manager.py"", line 127, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/query.py"", line 348, in create
    obj.save(force_insert=True, using=self.db)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/base.py"", line 734, in save
    force_update=force_update, update_fields=update_fields)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/base.py"", line 762, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/base.py"", line 846, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/base.py"", line 885, in _do_insert
    using=using, raw=raw)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/manager.py"", line 127, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/query.py"", line 920, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py"", line 974, in execute_sql
    cursor.execute(sql, params)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/backends/utils.py"", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/backends/utils.py"", line 64, in execute
    return self.cursor.execute(sql, params)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/utils.py"", line 97, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File ""/home/vagrant/ENV/local/lib/python2.7/site-packages/django/db/backends/utils.py"", line 64, in execute
    return self.cursor.execute(sql, params)
DataError: value too long for type character varying(5)
}}}

This is particularly relevant in the admin app, where the {{{LogEntry}}} model has a {{{object_repr}}} field with `max_length=200` that's prone to fail whenever a user does something on a model with a potentially big `repr` string (which is exactly how I came across this bug).

IMHO this has to do with how non-ascii characters are represented in a ASCII database."	Uncategorized	closed	Database layer (models, ORM)	1.8	Normal	invalid			Unreviewed	0	0	0	0	0	0