Ruby how to make search filters case insensitive

Question

I am building an app that has search fields how can I make search filters in my app case insensitive. Can I accomplish this in the following block of code:

<div class="filter">
  <%= form_tag posts_path, method: :get do %>
  <%= label_tag :bedrooms %>
  <%= text_field_tag :bedrooms, params[:bedrooms] %>

  <%= label_tag :bathrooms %>
  <%= text_field_tag :bathrooms, params[:bathrooms] %>

  <%= label_tag :neighborhood %>
  <%= text_field_tag :neighborhood, params[:neighborhood] %>

  <%= submit_tag "Search", name: nil %>
  <% end %>
</div>

Here is relevant code from controller

 class PostsController < ApplicationController
   before_action :set_post, only: [:show, :edit, :update, :destroy]
   def home
   end  

 def index
   @posts = Post.all.paginate(:page => params[:page], :per_page => 15)
   @posts = @posts.where(bedrooms: params["bedrooms"])if
   params["bedrooms"].present?
   @posts = @posts.where(bathrooms: params["bathrooms"])if
   params["bathrooms"].present?
   @posts = @posts.where(neighborhood: params["neighborhood"])if
   params["neighborhood"].present?
 end

This is not the relevant code. The relevant code is where you do the filtering itself, in a controller or model, comparing your filter params to the attributes of the objects in your model collections, or using them in database queries. — Amadan, May 26 '15 at 06:12
Thanks to all for help as you can see I am a new to all this. I do understand downcase a little but not sure how to use in this context. it's only the neighborhood field I have trouble with. — Mike Haslam, May 26 '15 at 06:33

score 0 · Accepted Answer · answered May 26 '15 at 06:13

0

posts = Post.find(:conditions => ["lower(bedroom) = ?", params[:bedrooms].downcase])

you can use lower and downcase to achieve that.

answered May 26 '15 at 06:13

Sachin R

11,606
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score 0 · Answer 2 · edited May 23 '17 at 10:30

Note: This writeup is based on the accepted answer to the question here.

If you are just coming in to the provided answers, here is a better explanation for using the lower function:

First of all, note: You could run into into incompatibilities - or worse: not realize some until damage is done, if you are using different Database for Development and different Database for Deployment. It's a bad idea™. Use the same RDBMS for development and production and save yourself the pointless trouble.

The lower() function works well both in SQlite and PostgreSQL and faster with its response.

In standard SQLite lower(X) only folds ASCII letters. For more, I quote the chapter Core Functions in the SQLite manual:

The lower(X) function returns a copy of string X with all ASCII characters converted to lower case. The default built-in lower() function works for ASCII characters only. To do case conversions on non-ASCII characters, load the ICU extension.

Better Emphasis here about PostgreSQL is that:
PostgreSQL lower(X) works with UTF-8 out of the box.

As a welcome side effect, you can speed up that query in PostgreSQL with an index on the expression lower(style), which will be faster than using ILIKE and a basic index on style.

Also, since PostgreSQL 9.1 you can use a GIN or GIST index with the pg_trgm extension to speed up any LIKE and ILIKE query - trigrams are case-insensitive. Detailed instructions and links in this related answer:

Similar UTF-8 strings for autocomplete field

This writeup is adapted from answers in Stackoverflow and basically by Erwin Brandstetter

score -1 · Answer 3 · answered May 26 '15 at 06:19

-1

you can use ilike in database Query.

Post.where("bedrooms ilike \"#{params[:bedrooms]}\" and bathrooms ilike \"#{params[:bathrooms]}\" and neighborhood ilike \"#{params[:neighborhood]}\"")

answered May 26 '15 at 06:19

Kamesh

1,435
1
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Ruby how to make search filters case insensitive

3 Answers3