Search through .select().group().distinct possible? - ruby-on-rails

Question

I want to create a search select that works on unique names through grouping...
The goal is to find duplicates to then use as a search parameter.
I want to find LineItem's :store_title's that match so I can create a select drop down for a way to search through LineItem's that match the specific :store_title.
Example:
LineItem DB:
line_item.title = "Hello"
line_item.title = "Hello"
line_item.title = "Okay"
line_item.title = "Bar"
I want to have a drop down select_tag in a search for the following:
[select]
"Hello"
"Okay"
"Bar"
And append all results that match LineItem.title of those which is selected.
I tried a few ways:
I so far have been able to get the unique drop down select field to "work" but not sure if it is the right way because it creates an array:
Controller:
#vendor_line_items = LineItem.where(vendor_id: #vendor.id).select(:store_title).group(:store_title).distinct
if params[:search]
#orders = Order.line_item_search(params[:search]).joins(:line_items).where(line_items: {vendor_id: #vendor.id})
end
ORders Model:
def self.line_item_search(search)
scope = joins(:line_items)
line_items = scope.where(line_items: { id: LineItem.where(store_title: "#{search.downcase}") })
line_items
end
View:
<%= form_tag vendor_orders_path, :method => 'get' do %>
<%= collection_select(:search, params[:search], #vendor_line_items, :store_title, :store_title, {}, {class: "form-control-sm col-5"})%>
<%= submit_tag "Search", :name => nil, class: "btn btn-primary btn-sm" %>
<% end %>
Error:
Undefined method 'downcase' for ["store_title"]:Array:
Can I alter my model to allow the array, or should i be finding the unique store titles another way?

Answer 1

If you just want to downcase the strings in that array, you could do something like this:
line_items = scope.where(line_items: { id: LineItem.where(store_title: search.map(&:downcase)) })
That will provide a list of downcased strings to your query.

Answer 2

I tried finding a way to remove the brackets before searching so the brackets were not present in the search parameters but couldn't figure it out.
Doing...:
line_items = scope.where(line_items: { id: LineItem.where(store_title: "#{search.join(', ')}") })
Solved it. This removes the brackets before searching the DB and works.
**
UPDATE:
**
View for response and answer to my issue:
Rails search form through arrays doesn't work on second search attempt