How to build index from model

rubyonrails-talk
1

Hi,

I have a application where I have a book model. I have a book controller, it has an action named "index_titles"

What should I write in the action of this controller to get a list with the distinct first letters for each book model in the view ?

For example when I have five books:

"Amazing title" "Bookworm is comming" "Basic for beginners" "Denial of service" "UPS development guide"

I will have four links in the view with the anchors "A", "B", "D" and "U" respectively.

I'm a experienced PHP developer, but I'm a newcommer to Ruby. What is the optimal rails way to accomplish this ?

Regards

2

astropanic wrote:

Hi,

I have a application where I have a book model. I have a book controller, it has an action named "index_titles"

What should I write in the action of this controller to get a list with the distinct first letters for each book model in the view ?

For example when I have five books:

"Amazing title" "Bookworm is comming" "Basic for beginners" "Denial of service" "UPS development guide"

I will have four links in the view with the anchors "A", "B", "D" and "U" respectively.

I'm a experienced PHP developer, but I'm a newcommer to Ruby. What is the optimal rails way to accomplish this ?

Regards

Something like this in your controller (assuming you're on Rails 2.1 or later):

def index_titles   @first_letters = Book.all(:select => 'title', :order => 'title').map {

book> book.title.first }

end

This code fetches the title of every book (in alpha order) and extracts just the first letter of each title. Be sure to have an index on the title column.

Then iterate on @first_letters in your view to render a link to each letter.

Hope that helps!

Jeremy http://jeronrails.blogspot.com

3

Thanks Man, It works nice :slight_smile:

Regards