Alan Reid

Hoping this displays right, this is what my table is like (minus the date fields) basically this shows that have 3 products in Venue ID 1 and 1 product with Venue ID 2

id  venue_id    product_id  price   stock_level     
1    1         5             0      NULL    
2    1         1             0      NULL    
3    2         1             0      NULL
4    1         4             0     NULL 

Using this code below i can return a list of items in from the DB and display a list of products that are in a venue's back bar. This works. But i am sure there is a better way to do it.

def show
    # Look up Venue
    @venue = Venue.find(params[:venue_id])

    if !@venue.nil?
      # Venue found look up back bar items
      @products_in_backbar = BackBar.select(:product_id).where(:venue_id => @venue.id)
      @products = Product.where(id: @products_in_backbar)
    else
      #Redirect to Venue page
      redirect_to venues_path
    end
    return
  end

Yeah, a product can be part of multiple bar bars, and a back bar can have more than 1 product.

I thought that having a back bar table would make things easier haha. The reason being is each product could have a different price per venue - yeah it's a crazy system i am working on, but fun lol

I think I understand why you're both saying I need a back_bar_id on the product table. And i think this is where the confusion is occurring, on my part.

The association I have is theproduct_id on the BackBar table, goes with the id on the Product table. so I guess the Product class 'has_many :back_bars' as thats where the association goes?

Maybe I am not explaining it right then.

Basically, this is the journey.

• A user finds a product, they first select the venue and then add it to the BackBar for that venue.
• This gets stored in the back_bars table as detailed above. It stores the venue_id and product_id

What i am trying to do, is similar to the Articles issue i had originally. Where I am getting back a list of items that are associated to a venue_id from the back_bar table. This provides me with a product_id with this I can get back the details of that product to display in a list in on the venue's back bar page.

This is the code i am now using and is working... but as with the articles method i am sure it can be simplified.

(im not sure how to do comments on here)

def show
    //Look up Venue
    @venue = Venue.find(params[:venue_id])

    if !@venue.nil?
      //Venue found look up back bar items
      @products_in_backbar = BackBar.select(:product_id).where(:venue_id => @venue.id)
      @products = Product.where(id: @products_in_backbar)
    else
      //Redirect to Venues page
      redirect_to venues_path
    end
    return
  end

Yeah I got that there was a missing column in the DB but having the 'back_bar_id' on the products table makes no sense.

A backbar can have many products, but belongs to a venue. Thus the backbar references the venue and product as per my previous posts.

I tried to do the same as we did for articles
But it just doesn't want to work and I can't see why

This is the table for back bar. Basically I am adding a venue_id and product_id when a user adds a product to the back bar.

create_table "back_bars", force: :cascade do |t|
    t.integer  "venue_id"
    t.integer  "product_id"
    t.decimal  "price",               default: "0.0"
    t.integer  "stock_level"
    t.integer  "last_ordered_amount"
    t.datetime "last_ordered_at"
    t.boolean  "active",              default: false
    t.datetime "created_at",                          null: false
    t.datetime "updated_at",                          null: false
    t.index ["product_id"], name: "index_back_bars_on_product_id", using: :btree
    t.index ["venue_id"], name: "index_back_bars_on_venue_id", using: :btree
  end

It would seem thats not quite right, I am getting this error...

PG::UndefinedColumn: ERROR:  column products.back_bar_id does not exist
LINE 1: SELECT  1 AS one FROM "products" WHERE "products"."back_bar_...
                                               ^
: SELECT  1 AS one FROM "products" WHERE "products"."back_bar_id" = $1 LIMIT $2

Cheers Jacob the second one makes more sense as each venue can only have one backbar.

That's interesting that products doesn't need anything to associate it. Maybe I need to read up more of a few of these concepts.

Chris,
I am trying to get this to include product details too, like we did above but for some reason i can't get it to work :/ could you see what i am missing please?

I am Getting a list the items in a backbar, which works fine, until i add in the includes() bit to get the extra details. I really can't get my head around includes(). lol

@products = BackBar.where(:venue_id => @venue.id).includes(:product)

This @products = BackBar.where(:venue_id => @venue.id) returns a list of items which are in the BackBar table, in there are 2 fields which are referenced venue_id and product_id -- Returns id: 1, venue_id: 1, product_id: 5

class BackBar < ApplicationRecord
  belongs_to :product
  has_many :venues

end

class Product < ApplicationRecord
  has_many :back_bars

end

class Venue < ApplicationRecord
  belongs_to :back_bar
end

does it have to be "Products_count"?

So i would set up the counter cache like so?

belongs_to :category counter_cache: true

The i could use the Category.where("products_count > 0") query. The i assume with those results i could get the products using 'includes(:product)' like we did before?

That's a typo on here where I typed it out. In the code it says .products.any. Updated the post, thanks for spotting

Hi again,
I want to know if there is a better way to get a list of categories which only have products.

I have tried to do @categories = Category.where(category_type: 'product').order(name: :asc).products.any but that seems to error and i am not sure why.

My Category has_many :products and my product belongs_to :category so i assumed this would work.

In my controller i am am getting a list of categories.

def index
  @categories = Category.where(category_type: 'product').order(name: :asc)
end

Then populating them on the page like as per below... now this work but its dirty and ends up with loads of calls to the DB which i don't personally like haha.

<% @categories.each do |category| %>
  <% if category.products.any? %>
    <div class="pad1 list-row">
      <div class="space-left4 pad1x row-details">
        <!-- Details -->
        <div class="details-name"><%= category.name %></div>
        <div class="details-sub">Products: <%= category.products.count %></div>
      </div>
      <div class="row-actions"></div>
    </div>
  <% end %>
<% end %>

Yeah haha I am getting there, can't believe how far i have come! Not to mention how i understand Rails better in 6 months compared to 8 years coding .NET!

would this be the same if i wanted to get a variants volume type?
Would i need to add , through: : products on the has_one :volume_types in the product_variant model

I have the following...

Product Model

product
has_many :product_variants, dependent: :destroy

Variant Model

product_variant
belongs_to :product
has_one :volume_types

# table has: volume_type_id

Volume Type Model

volume_type
belongs_to :product_variant

#table: volume_types
#t.string "short_name"

Chris, can I just have a direct link to your brain, please? haha

Hi again :)
I would like to know how to get my routes how i want them haha as we all do :) Basically i want to get the edit variant URL to be like /products/:product_id/variants/:variant_id

instead of /products/:product_id/variants/edit

I have used the code below to get my routes, however its not doing what i thought it might.

# Products routing
resources :products do
  resource :variants, module: :products
end

This gives me the following routes...

product_variants        POST   /products/:product_id/variants(.:format)      products/variants#create
new_product_variants    GET    /products/:product_id/variants/new(.:format)  products/variants#new
edit_product_variants   GET    /products/:product_id/variants/edit(.:format) products/variants#edit
                        GET    /products/:product_id/variants(.:format)      products/variants#show
                        PATCH  /products/:product_id/variants(.:format)      products/variants#update
                        PUT    /products/:product_id/variants(.:format)      products/variants#update
                        DELETE /products/:product_id/variants(.:format)      products/variants#destroy

Chris, we really need a like or kudos button you solved my issue, but others provide some great input too so they should get rewarded as well ;)

Guys thank you all so much for the extended discussion on this topic. Its really useful, and nice again more learning for me :D.

I have started to use it a lot else where in the site so it could be useful to have some of the lookups like this. I can also use this elsewhere in the app for other lookups.

Chris's example would work really well for me as I am using a similar lookup for users who don't manage the brands, but only follow them. So i could in theory retrieve articles for both there :)

James you have a article i could look at regarding this?