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" <[email protected] <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" <[email protected] <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 <[email protected] > <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" <[email protected] > <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 [email protected] > <javascript:>. > >>>>> To unsubscribe from this group, send email to > >>>>> [email protected] <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 [email protected] > <javascript:>. > >>> To unsubscribe from this group, send email to > >>> [email protected] <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. 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