ruby on rails - HABTM Relationship and Named Scopes -


I am working on this for a while and I do not know where the error is there.

I have a user model (: name, password, email), and event model (: name,: etc.) and interest model (: name) [> all singular & lt;]

Then I created two joining tables -> User lists and Events; Each has no primary key and only includes user_id / interest_id and event_id / interest_id. [> Plural and lieutenant;]

My model has HABTM relationships such as 

  user.rb = & gt; Has_and_belongs_to_many: Interests event.rb = & gt; Has_and_belongs_to_many: Interest interest.rb = & gt; Has_and_belongs_to_many: User has_and_belongs_to_many: events events_interests.rb = & gt; Has_and_belongs_to_many: Interests have_and_belongs_to_many: events_worlds.rb = & gt; Has_and_belongs_to_many: The user has__and_bangs_to_many: interests

Whew..ok So I wanted to create a named_scope, which looks for all the events that share interest with all special events. Here's some code that has helped me. 

  Named_Space: shares_interest_with_user, lambda {| User | {: Johns = & gt; "LEFT JOIN events_interests ei ON ei.event_id = Event.id" + "LEFT zone users_interests ui ON ui.interest_id = ei.interest_id" ,: conditions = & gt; ["Ui.user_id =?", User]}}

when I get the controller => 

  @user = User.find (1) @events = Event.shares_interest_with_user (@user)

I get a SQL error: "There are no such columns: Event.id: SELECT" events ". * Join the left of" events "events_interests Ei ON Ee.event_id = ........... "

Now I am sure the event model has an ID and I think all the column names are correct..at any What is it?

I recommend that you go away from HABT and instead of is_I: through .

The difference written by the SO user is explained here.


Comments

Post a Comment

Popular posts from this blog

sql - dynamically varied number of conditions in the 'where' statement using LINQ -

I am using my first project LINQ (in mvc), so maybe there's something very simple that I remember. However, a day of searching and experimenting does not work, so it works. I am trying to write a LINQ query (Linux to SQL) in which in many cases where the statement is different from an OR or an AND. We do not know how many conditions are going in the query till runtime. This search is for filter control, where the user can choose multiple criteria for filtering. Select from table where table.col = 1 or table.col = 2 or table.col = 7 .... 'Other number of conditions Before I just create the SQL query as a string, while looping over all the situations. However, it seems that there should be a good way to do this in LINQ. I tried to use Expression trees, but they had a second thought for this moment on my head, where the lambda function was to be executed inside the statement such as: values ​​for matchingRows = matchingRows for each value Where (function (row) row.c...
Read more

asp.net mvc - Dynamically Generated Ajax.BeginForm -

I have a problem with ASP.NET MVC Ajax forms. I generate many Ajax form in a table such as: & Lt; Input type = "submit" name = "activity" value = "add activity" / & gt; & Lt;%}% & gt; & Lt; / TD & gt; & Lt; / TR & gt; & Lt;%}% & gt; So far so good. When I post one of those forms, it gives a partial view in a div, and in this new partial view a new Ajax Beginnform (which is not in Genesis form) This second Ajax Beginnorf is exactly like the ones I got on the table, but when I post it, I do not get the "Ajax Post", but a normal post that sends me to a new page, I do not know whether the two Ajax forms What is the reason for the difference between, why is it the "dynamically generated" Ajax form behaves like a normal HTML form? By the way, I know that I can do it in different ways using javascript, but I would like to understand whether it can only be done using MVC helplars and Ajax lib...
Read more

Debug on symbian -

I am using trk for phone debug This works well for the Holorld project But when I start the project in phone debug mode 1) the load failed 2) TrkProtocolPlugin: to target the specified file Failure (please verify If any body understands what problem I am experiencing, then this problem helps me Pre-release If the application has the privileges assigned (with the appropriate certificate) itemprop = "text" > In your case, I will check: / li> If there is no conflict of application ID with any other application of device If there are problematic commands in the installation package (for example copy copy for non-accessible directories)
Read more