PostgreSQL primary (sequence) key issue (Ruby/Rails)

On 01/03/07, Andrew Madu < andrewmadu@gmail.com> wrote:

Hi Dave,
my apologies for contacting you off list but i'm having a spot of bother
with postgreSQL sequence setup in rails. In addition to what is mentioned
below, I have place the following line of code in my

The definition of primary key explicitly states that it can't be null.
You are trying to pass a null to user_id which won't work.

Joshua D. Drkae

environment.rbdocument:

# Include your application configuration below
ActiveRecord::Base.pluralize_table_names = false
ActiveRecord::Base.set_sequence_name

What I am overlooking here?

--
Regards

Andrew

---------- Forwarded message ----------
From: Andrew Madu < andrewmadu@gmail.com>
Date: 01-Mar-2007 15:28
Subject: Re: PostgreSQL primary (sequence) key issue
To: rubyonrails-talk@googlegroups.com

Hi,
I've followed the example given here:

http://ar.rubyonrails.com/classes/ActiveRecord/Base.html#M000367

and implemented set_sequence_name "seq_name" in my class. When I try to
update the user table with a new row from:

http://localhost:3000/usertbl/new

I get the following error message:

RuntimeError: ERROR C23502 Mnull value in column "user_id"
violates not-null constraint

FexecMain.c L1795 RExecConstraints: INSERT INTO usertbl

What am I overlooking here?

Also coud possibly give me any clues on how to setup an 'assigned'
primary
key in an ActiveRecord class?

--
Regards

Andrew

On 01/03/07, Andrew Madu <andrewmadu@gmail.com> wrote:

Hi,
I have a sequence set up on one of my tables called seq_user_mytable. I
tried the following with no joy:

set_primary_key "user_id", :sequence => "seq_user_mytable" and:

ActiveRecord:: Base.seq_user_mytable

again with no joy. How do I implement a sequence in Rails/ActiveRecord?

--
Regards

Andrew

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Joshua D. Drake wrote:

On 01/03/07, Andrew Madu < andrewmadu@gmail.com> wrote:

Hi Dave,
my apologies for contacting you off list but i'm having a spot of bother
with postgreSQL sequence setup in rails. In addition to what is mentioned
below, I have place the following line of code in my

The definition of primary key explicitly states that it can't be null.
You are trying to pass a null to user_id which won't work.

Joshua D. Drkae

In MySQL that is traditionally how you tell the RDBMS to use the
auto_increment to generate the value. Postgres correctly doesn't allow
that (since you might actually try to set a field to NULL accidentally
in which case an error is expected).

The portable (and correct) way to do it is to use the DEFAULT keyword
like this:

INSERT INTO some_table (id_field) VALUES (DEFAULT);

I just tested on MySQL 5.0.32 and that syntax works fine.

--

Russ.

The portable (and correct) way to do it is to use the DEFAULT keyword
like this:

INSERT INTO some_table (id_field) VALUES (DEFAULT);

Alternatively, for columns for which you have no value, don't specify them
at all in the insert.

--
Scott Ribe
scott_ribe@killerbytes.com
http://www.killerbytes.com/
(303) 722-0567 voice