Comments on: How to display a collection grouped by an attribute value in Rails

By: Miquel Herrera

Miquel Herrera — Mon, 28 Dec 2009 13:30:01 +0000

The form eaten my html example :(

I hope you get the idea

By: Miquel Herrera

Miquel Herrera — Mon, 28 Dec 2009 13:28:51 +0000

It is always interesting to learn new tricks but in this case I would consider more efficient to get the data ready to use straight from the DB rather than getting the same data and reorganize in memory. I would do something like this:

@authors = Author.find :all, :include => :quotes, :order => :name

this returns an array of authors and pre-load their quotes using two sql instances such as:

SELECT * FROM `authors` ORDER BY name;
SELECT `quotes`.* FROM `quotes` WHERE (`quotes`.author_id IN (1,2,3,…));

in the view you just loop all authors and their quotes:

By: Chess

Chess — Mon, 20 Oct 2008 03:08:03 +0000

Thanks for this, very helpful for us who don’t yet know all the nooks and crannys in rails and ruby!

By: Frank

Frank — Sun, 19 Oct 2008 13:20:40 +0000

Grant, this is even better than @authors.keys.sort.each, thanks for sharing.

By: Grant Hutchins

Grant Hutchins — Sun, 19 Oct 2008 07:05:27 +0000

You can also do:

@authors.sort.each do |author_name, quote|

because Hash#sort returns an array of 2-value arrays of the form [key, value]