StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PORuby - Difference between :variable and @variable
primarykey
Id
7211724
data
AcceptedAnswerId
7211781
AnswerCount
1
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2011-08-27T00:22:43.437
FavoriteCount
5
LastActivityDate
2011-08-27T00:59:15.303
LastEditDate
2017-05-23T12:14:34.623
LastEditorUserId
-1
OwnerUserId
897491
ParentId
0
PostTypeId
1
Score
5
ViewCount
4001
LastEditorDisplayName
text
Body
As a Ruby on Rails newbie, I understand that the "@" and ":" references have different meanings. I saw <a href="https://stackoverflow.com/questions/3538575/whats-the-difference-between-and-variable-variable-and-vari">this post</a> in SO, which described some of the differences. <ol> <li>@ indicates a instance variable (e.g., @my_selection)</li> <li>: indicates an alias (e.g., :my_selection)</li> </ol> I ran into a situation where I had a standard MVC page, similar to all of the other forms/pages in my webapp. html.erb snippet <pre><code><%= form_for @my_selection do |f| %> </code></pre> route.rb snippet <pre><code>resources :my_selections </code></pre> When I attempt to access this page, I get this error: <pre><code>NoMethodError in selections#create Showing C:/somedir/myapp/app/views/my_selections/index.html.erb where line #16 raised: undefined method `my_selection_index_path' for #<#<Class:0x1197e5676>:0x25439c3b> </code></pre> Line 16 is the form snippet shown above. All of my other forms/pages in the same web app are set up in exactly the same way and are working fine. However, once I changed the erb form reference to :my_selection, this error went away and my page behaved normally. Questions: <ol> <li>Is my understanding of the difference between :my_selections and @my_selections correct?</li> <li>Why would switching to :my_selection resolve my original error?</li> </ol>
Tags
<ruby><ruby-on-rails-3>
Title
Ruby - Difference between :variable and @variable
singulars
PostAcceptedAnswerId
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
PostParentId
1. This table or related slice is empty.
PostTypePostTypeId
1. PTQuestion
UserLastEditorUserId
1. USCommunity
UserOwnerUserId
1. USJW8
plurals
PostLinksPostIdRelatedPostId
1. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
PostLinksRelatedPostIdPostId
1. PL
 singulars
 LinkTypeLinkTypeId
 LTLinked
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
 singulars
 PostTypePostTypeId
 PTAnswer
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PORuby - Difference between :variable and @variable
 UserUserId
 USennuikiller
 VoteTypeVoteTypeId
 VTFavorite
2. VO
 singulars
 PostPostId
 PORuby - Difference between :variable and @variable
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
3. VO
 singulars
 PostPostId
 PORuby - Difference between :variable and @variable
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
CommentsPostId
1. This table or related slice is empty.

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.