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
15513	CharField ForeignKey forced to int during lookup  in get_prep_value in django.db.models.fields	harijay	nobody	"I created a small test case to illustrate the problem.

{{{
>>> c = Child.objects.filter(parents_ssn=""2354234234"")

Suceeds!

>>> print c[0].name
werwer sdfgsdg

The following lookup fails

>>> cfails = Child.objects.filter(parents_ssn=""g354234234c"")
Traceback (most recent call last):
  File ""<console>"", line 1, in <module>
  File ""/home/hari/djtrunk/django/db/models/manager.py"", line 141, in filter
    return self.get_query_set().filter(*args, **kwargs)
  File ""/home/hari/djtrunk/django/db/models/query.py"", line 550, in filter
    return self._filter_or_exclude(False, *args, **kwargs)
  File ""/home/hari/djtrunk/django/db/models/query.py"", line 568, in _filter_or_exclude
    clone.query.add_q(Q(*args, **kwargs))
  File ""/home/hari/djtrunk/django/db/models/sql/query.py"", line 1170, in add_q
    can_reuse=used_aliases, force_having=force_having)
  File ""/home/hari/djtrunk/django/db/models/sql/query.py"", line 1105, in add_filter
    connector)
  File ""/home/hari/djtrunk/django/db/models/sql/where.py"", line 67, in add
    value = obj.prepare(lookup_type, value)
  File ""/home/hari/djtrunk/django/db/models/sql/where.py"", line 316, in prepare
    return self.field.get_prep_lookup(lookup_type, value)
  File ""/home/hari/djtrunk/django/db/models/fields/related.py"", line 136, in get_prep_lookup
    return self._pk_trace(value, 'get_prep_lookup', lookup_type)
  File ""/home/hari/djtrunk/django/db/models/fields/related.py"", line 209, in _pk_trace
    v = getattr(field, prep_func)(lookup_type, v, **kwargs)
  File ""/home/hari/djtrunk/django/db/models/fields/__init__.py"", line 882, in get_prep_lookup
    return super(IntegerField, self).get_prep_lookup(lookup_type, value)
  File ""/home/hari/djtrunk/django/db/models/fields/__init__.py"", line 292, in get_prep_lookup
    return self.get_prep_value(value)
  File ""/home/hari/djtrunk/django/db/models/fields/__init__.py"", line 876, in get_prep_value
    return int(value)
ValueError: invalid literal for int() with base 10: 'g354234234c'


################
models.py has:
################

from django.db import models

class Parent(models.Model):
    id = models.IntegerField(primary_key=True)
    name = models.CharField(max_length=384, blank=True)
    ssn = models.CharField(max_length=768, blank=True)
    class Meta:
        db_table = u'Parent'
        app_label = u'mydjapp'

class Child(models.Model):
    id = models.IntegerField(primary_key=True)
    name = models.CharField(max_length=384, blank=True)
    parents_ssn = models.ForeignKey(Parent, null=True, db_column='parents_ssn', blank=True)
    class Meta:
        db_table = u'child'
        app_label= u'mydjapp'

~                                       
#####################
The database columns are:
######################

mysql> select * from Parent;
+----+--------------+--------------+
| id | name         | ssn          |
+----+--------------+--------------+
|  1 | Aefwesk baob | 42s354234234 |
|  2 | Ask bob      | 2354234234   |
|  3 | Seelan Cyata | 2354234234c  |
|  4 | Hdel Abnot   | g354234234c  |
+----+--------------+--------------+
4 rows in set (0.00 sec)


mysql> select * from child;
+----+----------------+-------------+
| id | name           | parents_ssn |
+----+----------------+-------------+
|  1 | werwer sdfgsdg | 2354234234  |
|  2 | Hyadr Abnot    | g354234234c |
+----+----------------+-------------+
2 rows in set (0.00 sec)



##########################
The raw SQL test was setup :
#######################
CREATE TABLE `Parent` (

  `id` int(11) NOT NULL,
  `name` varchar(128) DEFAULT NULL,
  `ssn` varchar(256) DEFAULT NULL,
  PRIMARY KEY (`id`),

  KEY `parents_ssn_fk` (`ssn`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |


CREATE TABLE `child` (

  `id` int(11) NOT NULL,
  `name` varchar(128) DEFAULT NULL,
  `parents_ssn` varchar(256) DEFAULT NULL,
  PRIMARY KEY (`id`),

  KEY `parents_ssn` (`parents_ssn`),
  CONSTRAINT `child_ibfk_1` FOREIGN KEY (`parents_ssn`) REFERENCES `Parent` (`ssn`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
}}}"		closed	Database layer (models, ORM)	dev		invalid			Unreviewed	0	0	0	0	0	0