Working with models, efficent queries

Rails
1

i have a model with 35000 entries in the database. I was using a unique
string as the primary key. Right now I am using the order method to
return
the model objects in
order. I’d like to know what is good practice ( efficient ) and how to
return X entries at a time instead of all at once. Right now I’m using
the
index method of a controller along with the order method to return the
entries, and then iterating through them in the view.

class StoreController < ApplicationController
def index
@dicts = Dict.order(:key)
end
end

Store#index

Find me in app/views/store/index.html.erb

<% @dicts.each do |word| %>
<%= word.key %>
<%end %>

I’d also like to know a little more about how conrtrollers work with the
database. Is a new store controller instanced everytime a route is
directed
to it? If so am I continually querying the database for those 35000
entries, or is one instance of the controller generated, and one request
made. I have read some of the rails guides, and read quite a bit of
agile
web dev with rails 4, but haven’t found the answer to my questions. Do
you
think you know a reference you would recommend I read?

2

You need pagination, visit this 1

On Wed, Dec 11, 2013 at 4:29 AM, Colin W. [email protected]
wrote:

 @dicts = Dict.order(:key)

You received this message because you are subscribed to the Google G.
“Ruby on Rails: Talk” group.
To unsubscribe from this group and stop receiving emails from it, send an
email to [email protected].
To post to this group, send email to [email protected].
To view this discussion on the web visit

https://groups.google.com/d/msgid/rubyonrails-talk/0b1b8461-ca5a-4442-acd4-b32fbfac1bf4%40googlegroups.com

.
For more options, visit https://groups.google.com/groups/opt_out.

–
greatghoul http://www.g2w.me - Ask and Learn!

3

On Tuesday, December 10, 2013 8:29:17 PM UTC, Colin W. wrote:

i have a model with 35000 entries in the database. I was using a unique
string as the primary key. Right now I am using the order method to return
the model objects in
order. I’d like to know what is good practice ( efficient ) and how to
return X entries at a time instead of all at once. Right now I’m using the
index method of a controller along with the order method to return the
entries, and then iterating through them in the view.

Typically you load one page of results at a time. kaminari and
will_paginate are 2 popular ways of doing this. Under the hood they are
just setting limit and offset query

I’d also like to know a little more about how conrtrollers work with the
database. Is a new store controller instanced everytime a route is directed
to it? If so am I continually querying the database for those 35000
entries, or is one instance of the controller generated, and one request
made. I have read some of the rails guides, and read quite a bit of agile
web dev with rails 4, but haven’t found the answer to my questions. Do

a new controller is instantiated with each request. so your code hits
the
database for every single page view (which you can easily prove to
yourself
by adding a breakpoint or logger statements to the body of your
controller
method or watching the queries stack up in the log file

Fred