Databases
StackOverflow2013
Postsdbo
PORails 3.2 - collection_select Adding A Null Entry In The First Position Of My Array
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PORails 3.2 - collection_select Adding A Null Entry In The First Position Of My Array
    primarykey
    data
    text
    <p>I have a Ruby on Rails 3.2.13 application where I have a collection_select statement. The collection_select statement is in a fields_for statement where I gather selected ids from the collection_select and use them to populate another table. The problem I am having is that the collection_select statement adds a null id entry in the array that stores the collection of selected ids.</p> <p>Here is my code in my view:</p> <pre><code>&lt;%= f.fields_for :media_topics do |media_topic| %&gt; &lt;%= media_topic.label :topic, "Topics" %&gt;&lt;%= media_topic.collection_select(:topic_id, Topic.order("name_en"), :id, :name_en, {}, {multiple: true}) %&gt; &lt;% end %&gt; </code></pre> <p>Here is an example of how the array looks after selecting two options:</p> <pre><code>"media_topics_attributes"=&gt;{"0"=&gt;{"topic_id"=&gt;["", "2", "47"], "id"=&gt;"1895"}} </code></pre> <p>I would think the array should only have two ids, "2" and "47". The null value is causing a problem with updating my nested attributes because of an error saying that the value can't be blank. When the edit view is displayed for a row with related rows that exists the correct records in the collection_select are selected and highlighted in the list as expected.</p> <p>How do I change the collection_select statement where it does not add the null entry? I do not allow any rows on the MediaTopic model to be added with topic_id equal to null. I have been researching this for several days. I found one where a person had a similar issue but none of the solutions on that question work to solve the problem.</p> <p>Any help would be appreciated.</p>
    singulars
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USPamela Cook - LightBe Corp
    plurals
    1. This table or related slice is empty.
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. PORails 3.2 - collection_select Adding A Null Entry In The First Position Of My Array
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PORails 3.2 - collection_select Adding A Null Entry In The First Position Of My Array
      1. USMatt
      1. VTFavorite
    1. COThis seems to be expected. Please see: github.com/rails/rails/issues/7289
      singulars
      1. PORails 3.2 - collection_select Adding A Null Entry In The First Position Of My Array
      1. USvee
    2. COI wondered if this is normal. It looks like it will be corrected in Rails 4. Initially I was doing this manually before I decided to try using accepts_nested_attributes_for for the first time. I had hoped to figure out how to remove that blank entry before doing update_attributes for the model but so far I have not had any luck. I will submit another question regarding my problem with skipping that blank entry until I upgrade the application to Rails 4. Thanks so much for the information.
      singulars
      1. PORails 3.2 - collection_select Adding A Null Entry In The First Position Of My Array
      1. USPamela Cook - LightBe Corp
    3. COI recently rewrote my Rails application using Rails 4.0.0. In the first set of brackets I added include_hidden: false and the null entry does not appear in the array.
      singulars
      1. PORails 3.2 - collection_select Adding A Null Entry In The First Position Of My Array
      1. USPamela Cook - LightBe Corp
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload