Rails - Nov 2007 - Querying and returning an array rather than an object?

I''m trying to write an application where people can vote on things,
and I want to make sure a person can''t vote twice.  Pretend
''user'' is
voting on various objects. I was thinking about something like this:

v = user.votes.find(:all, :select => ''object_id'').

if v.contains?(object_a.id) then already_voted_a
if v.contains?(object_b.id) then already_voted_b
if v.contains?(object_c.id) then already_voted_c

etc...

But v won''t be an array of object ids, it will be an array of votes,
right? How do you think I should go about doing this?

They''re going to be many objects on a single page, so I only want to
do one database query.

Thanks!

Stedwick


--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

On 2 Nov 2007, at 14:27, Stedwick wrote:
>
> I''m trying to write an application where people can vote on
things,
> and I want to make sure a person can''t vote twice.  Pretend
''user'' is
> voting on various objects. I was thinking about something like this:
>
> v = user.votes.find(:all, :select => ''object_id'').
>
> if v.contains?(object_a.id) then already_voted_a
> if v.contains?(object_b.id) then already_voted_b
> if v.contains?(object_c.id) then already_voted_c
>
> etc...
>
> But v won''t be an array of object ids, it will be an array of
votes,
> right? How do you think I should go about doing this?
>
> They''re going to be many objects on a single page, so I only want
to
> do one database query.
>
Well if you do just want an array of values, you might be interested  
in the select_all or select_values methods provided by the connection  
(ie User.connection.select_values ''SELECT object_id from votes where  
user_id = 123'')

Fred

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---

Thanks!

I also realized I could probably use things like:

v.map!{|x| x.object_id}

or

v.flatten!.compact!

Those would probably work too, right?

On Nov 2, 10:29 am, Frederick Cheung
<frederick.che...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> On 2 Nov 2007, at 14:27, Stedwick wrote:
>
>
>
>
>
> > I''m trying to write an application where people can vote on
things,
> > and I want to make sure a person can''t vote twice.  Pretend
''user'' is
> > voting on various objects. I was thinking about something like this:
>
> > v = user.votes.find(:all, :select =>
''object_id'').
>
> > if v.contains?(object_a.id) then already_voted_a
> > if v.contains?(object_b.id) then already_voted_b
> > if v.contains?(object_c.id) then already_voted_c
>
> > etc...
>
> > But v won''t be an array of object ids, it will be an array of
votes,
> > right? How do you think I should go about doing this?
>
> > They''re going to be many objects on a single page, so I only
want to
> > do one database query.
>
> Well if you do just want an array of values, you might be interested
> in the select_all or select_values methods provided by the connection
> (ie User.connection.select_values ''SELECT object_id from votes
where
> user_id = 123'')
>
> Fred

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---