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
25312	Bug: AutoField backed by Postgres 9+ creates error condition	Stephan Doliov	nobody	"The essence of this bug report is that models.py creates an inherent conflict between default, autoincrementing id fields (AutoField) and what a postgres 9.x (9.4 in my case) assigns as the type for the auto incrementing field. When makemigration creates the sequence, the sequence is created as a big integer. However, the database table that uses the sequence (the id field) is created as an integer. So once the value of the sequence exceeds the maximum value of a 32 bit integer, the insert will fail.

Below is models.py code and some psql command line foo to illustrate the problem

{{{
import datetime
import hashlib
import os
from math import sqrt
from random import Random
from django.db import models
from django.db.models.query import Q
from django.utils.text import slugify
from djangoratings.fields import RatingField
from django_pgjson.fields import JsonBField
from django_images.models import Image as BaseImage
from django.utils import timezone

class EventName(models.Model):
  event_name = models.CharField(max_length=500, blank=False, null=False)
  event_desc = models.CharField(max_length=500, blank=False, null=True)
  event_creation_date = models.DateTimeField(auto_now_add=True,null=False)
  event_update_date = models.DateTimeField(auto_now=True,null=False)

  def __unicode__(self):
    return self.name

}}}

{{{
steves_app=> \d eventlogs_eventname_id_seq 
     Sequence ""public.eventlogs_eventname_id_seq""
    Column     |  Type   |           Value            
---------------+---------+----------------------------
 sequence_name | name    | eventlogs_eventname_id_seq
 last_value    | bigint  | 1
 start_value   | bigint  | 1
 increment_by  | bigint  | 1
 max_value     | bigint  | 9223372036854775807
 min_value     | bigint  | 1
 cache_value   | bigint  | 1
 log_cnt       | bigint  | 0
 is_cycled     | boolean | f
 is_called     | boolean | f
Owned by: public.eventlogs_eventname.id

steves_app=> \d eventlogs_eventname
                                        Table ""public.eventlogs_eventname""
       Column        |           Type           |                            Modifiers                             
---------------------+--------------------------+------------------------------------------------------------------
 id                  | integer                  | not null default nextval('eventlogs_eventname_id_seq'::regclass)
 event_name          | character varying(500)   | not null
 event_desc          | character varying(500)   | 
 event_creation_date | timestamp with time zone | not null
 event_update_date   | timestamp with time zone | not null
Indexes:
    ""eventlogs_eventname_pkey"" PRIMARY KEY, btree (id)
Referenced by:
    TABLE ""eventlogs_event"" CONSTRAINT ""eventlog_event_id_id_153f5722b6e1dffb_fk_eventlogs_eventname_id"" FOREIGN KEY (event_id_id) REFERENCES eventlogs_eventname(id) DEFERRABLE INITIALLY DEFERRED

fitcode_app=> alter sequence eventlogs_eventname_id_seq restart with 4294967297;
ALTER SEQUENCE
fitcode_app=> insert into eventlogs_eventname(event_name,event_desc,event_creation_date,event_update_date) values ('foo','bar',now(),now());
ERROR:  integer out of range

}}}
"	Bug	new	Uncategorized	1.7	Normal		AutoField, Postgres, Sequences		Unreviewed	0	0	0	0	0	0