Question

In my model I have

    class Alias
  include DataMapper::Resource


  belongs_to :user


  property :id, String, :key => true, :required => true, :unique => true

  validates_format_of :id, :with => /[0-9a-z\-]/i

end

In my controller:

def new
   @new_alias = @owner.aliases.new()
end
    def create 
         @owner = current_user
         @alias = @owner.aliases.create(params[:alias])
end

And in my view

<%= form_for @new_alias, :url => {:controller => "aliases", :action=>"create"} do |f| %> 
    <%= f.text_field :id, :placeholder => "Account name" %></br>
    <%= f.submit :value => "Create" %>
 <% end %>

For me it looks preatty normal, but when I’m trying to save new alias, it results with with:

ERROR:  null value in column "alias_id" violates not-null constraint

Processing by AliasesController#create
as HTML Parameters: {“utf8″=>”✓”,
“authenticity_token”=>”/token=”,
“alias”=>{“id”=>”IDNAME”},
“commit”=>”Create”} ~ SQL (0.632ms)
SELECT “id”, “encrypted_password”,
“remember_created_at”,
“reset_password_token”,
“reset_password_sent_at”,
“failed_attempts”, “unlock_token”,
“locked_at”, “sign_in_count”,
“current_sign_in_at”,
“last_sign_in_at”,
“current_sign_in_ip”,
“last_sign_in_ip”, “username”,
“email”, “name”, “country” FROM
“users” WHERE “id” IN (2) LIMIT 1 ~
SQL (0.491ms) SELECT “id” FROM
“aliases” WHERE “id” = ‘IDNAME’ ORDER
BY “id” LIMIT 1 Completed in 11ms ~
SQL (0.531ms) INSERT INTO “aliases”
(“id”, “user_id”) VALUES (‘IDNAME’, 2)
~ ERROR: null value in column
“alias_id” violates not-null
constraint (code: 33575106, sql
state: 23502, query: INSERT INTO
“aliases” (“id”, “user_id”) VALUES
(‘IDNAME’, 2), uri:
postgres:name@localhost:5432postgres?adapter=postgres&host=localhost&port=5432&username=name&password=pass&database=postgres&path=postgres&schema_search_path=public&encoding=utf8&template=template0)

DataObjects::IntegrityError (ERROR:
null value in column “alias_id”
violates not-null constraint ):
app/controllers/aliases_controller.rb:5:in
`create’

What could be the problem? I’m using rails3, postgres and datamapper.

Answer 1

Not familiar with rails internals, but your column’s definition must be so that it allow null values.