Naoko I ma facing the problem of updating primary key automatically in django with postgresql database
Could you please suggest what need to be done. Do we need to create a sequence for the table to achieve this. Hoping for your reply On Sunday, May 29, 2011 at 8:32:45 PM UTC+5:30, Naoko wrote: > > I was missing this from schema: > ALTER SEQUENCE tablename_colname_seq OWNED BY tablename.colname; > > Now everything is happy. Thank you! > > > On 5/28/11 8:32 AM, "Naoko Reeves" <naoko...@gmail.com <javascript:>> > wrote: > > > Malcolm, Thank you for your advice! > > I changed my model as follows: > > poll_key = models.AutoField(primary_key=True, db_column='poll_key') > > However, the result remain the same as shown below. If you could point > me out > > to right direction again, I would appreciate. Thank you very much for > your > > time. > > > >>>> from mysite.polls.models import Poll2 > >>>> p3 = Poll2(poll2_question='3') > >>>> p3.save() > >>>> p3.pk > > 4L > >>>> from mysite.polls.models import Poll > >>>> p5 = Poll(poll_question='5') > >>>> p5.save() > >>>> print p5.pk > > None > > > > > > On 5/28/11 12:23 AM, "Malcolm Box" <malco...@gmail.com <javascript:>> > wrote: > > > >> You need to tell django what the db column name for your pollkey field > is. > >> Look at the dbname field option in the docs. > >> > >> > >> Sent from my iPhone, please excuse any typos > >> > >> On 28 May 2011, at 05:13, Naoko Reeves <naoko...@gmail.com > <javascript:>> wrote: > >> > >>> I see if column is set to AutoField then Django won't send INSERT > poll_key > >>> as null. > >>> Now my problem is that it doesn't return newly assigned primary key > value > >>> for me if primary key name is _key instead of _id > >>> It looks as if sequence name is not understood correctly. > >>> Could you tell me if > >>> 1) I need to change sequence name to something else? Currently it is > >>> poll_key_seq > >>> 2) Is there a way to specify the sequence name? > >>> > >>> > >>> class Poll(models.Model): > >>> poll_key = models.AutoField(primary_key=True) > >>> poll_question = models.CharField(max_length=200, default='') > >>> > >>> class Poll2(models.Model): > >>> poll2_id = models.AutoField(primary_key=True) > >>> poll2_question = models.CharField(max_length=200, default='') > >>> > >>>>>> from mysite.polls.models import Poll2 > >>>>>> p3 = Poll2(poll2_question='3') > >>>>>> p3.save() > >>>>>> p3.pk > >>> 2L > >>>>>> p4 = Poll2(poll2_question='4') > >>>>>> p4.save() > >>>>>> p4.pk > >>> 3L > >>>>>> from mysite.polls.models import Poll > >>>>>> p5 = Poll(poll_question='5') > >>>>>> p5.save() > >>>>>> print p5.pk > >>> None > >>> > >>> > >>> On 5/27/11 5:31 PM, "Casey Greene" <csgr...@princeton.edu > <javascript:>> wrote: > >>> > >>>> Doesn't autofield with primary_key=True handle this for you (instead > of > >>>> making it an IntegerField): > >>>> > >>>> https://docs.djangoproject.com/en/1.3/ref/models/fields/#autofield > >>>> > >>>> Hope this helps! > >>>> Casey > >>>> > >>>> On 05/27/2011 07:22 PM, Naoko Reeves wrote: > >>>>> Hi, I have a Django newbie question. > >>>>> My goal is to auto increment primary key with non Django standard > column > >>>>> name. > >>>>> We are converting from existing database and primary key schema is > >>>>> "tablename_key" and not "id". > >>>>> I googled it and end up reaching to this ticket: > >>>>> https://code.djangoproject.com/ticket/13295 > >>>>> So I understand that there is work in progress but I wanted find work > >>>>> around.. > >>>>> > >>>>> 1. My first try was to let postgres handle it. > >>>>> > >>>>> my postgreSQL table looks like this: > >>>>> > >>>>> CREATE TABLE poll > >>>>> ( > >>>>> poll_key integer NOT NULL DEFAULT > nextval('poll_key_seq'::regclass), > >>>>> poll_question character varying(200) NOT NULL, > >>>>> poll_pub_date timestamp with time zone NOT NULL, > >>>>> CONSTRAINT poll_pkey PRIMARY KEY (poll_key) > >>>>> ) > >>>>> > >>>>> My model look like this: > >>>>> class Poll(models.Model): > >>>>> poll_key = models.IntegerField(primary_key=True) > >>>>> poll_question = models.CharField(max_length=200, default='') > >>>>> poll_pub_date = models.DateTimeField('date published', > >>>>> default=datetime.date.today()) > >>>>> class Meta: > >>>>> db_table = u'poll' > >>>>> > >>>>> I was hoping that with this, I could > >>>>> p = Poll(poll_question="Question 1?") > >>>>> p.save() > >>>>> > >>>>> but this fails because Django is actually sending the following > statement: > >>>>> INSERT INTO "poll" ("poll_key", "poll_question", "poll_pub_date") > >>>>> VALUES (NULL, 'Question 1?', NULL) > >>>>> > >>>>> > >>>>> 2. My Second attempt is then to add default to model > >>>>> > >>>>> Created a function to return sequence value > >>>>> from django.db import connection > >>>>> def c_get_next_key(seq_name): > >>>>> """ return next value of sequence """ > >>>>> c = connection.cursor() > >>>>> c.execute("SELECT nextval('%s')" % seq_name) > >>>>> row = c.fetchone() > >>>>> return int(row[0]) > >>>>> > >>>>> Calling like below works just fine. Everytime I call it, I get new > number. > >>>>> c_get_next_key('poll_key_seq') > >>>>> > >>>>> Then I modify Poll_key in Poll model as follows: > >>>>> Poll_key = models.IntegerField(primary_key=True, > >>>>> default=c_get_next_key('poll_key_seq')) > >>>>> > >>>>> I went to Django Shell and created first record. > >>>>> p1 = Poll(poll_question="P1") > >>>>> p1.poll_key > >>>>> # this will return let's say 37 > >>>>> p1.save() > >>>>> # saves just fine. > >>>>> > >>>>> # instantiating new object > >>>>> p2 = Poll(poll_question="P2") > >>>>> p2.poll_key > >>>>> # this also return 37. > >>>>> > >>>>> I know I must be doing something wrong... but could you pint me to > right > >>>>> direction? I am expecting p2.poll_key to return 38. > >>>>> Thank you very much for your help in advance. > >>>>> > >>>>> Naoko > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> -- > >>>>> You received this message because you are subscribed to the Google > >>>>> Groups "Django users" group. > >>>>> To post to this group, send email to django...@googlegroups.com > <javascript:>. > >>>>> To unsubscribe from this group, send email to > >>>>> django-users...@googlegroups.com <javascript:>. > >>>>> For more options, visit this group at > >>>>> http://groups.google.com/group/django-users?hl=en. > >>> > >>> > >>> -- > >>> You received this message because you are subscribed to the Google > Groups > >>> "Django users" group. > >>> To post to this group, send email to django...@googlegroups.com > <javascript:>. > >>> To unsubscribe from this group, send email to > >>> django-users...@googlegroups.com <javascript:>. > >>> For more options, visit this group at > >>> http://groups.google.com/group/django-users?hl=en. > >>> > > > -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscr...@googlegroups.com. To post to this group, send email to django-users@googlegroups.com. Visit this group at https://groups.google.com/group/django-users. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/313af2da-e5d0-4826-aa9b-9fe7e762674d%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
