Skip to main content

Loading Associations of associations using joins instead of includes


Imagine a Rails scenario where,User model has many associations.So it make look like:-

Use includes for lazy loading of all associations
Use joins to load all associations that exists

For example:-
                 A user has many orders.
                 Order has many images,videos,comments,testimonials,feedbacks,address,contact_details and annoucements.

So,to access a user having a request,with all orders having all associations,we will use the usual includes like :-

User.includes( { orders: [ { :address,:contact_details,:comments,annoucements,feedbacks: [:videos, :images] }] }) will load all users .

But,to get all users having all associations present,we can use Joins like:

User.joins( { orders: [ { :address,:contact_details,:comments,annoucements,feedbacks: [:videos, :images] }] }) will load all users with associations present.



Hope it helps :)



Comments

Post a Comment

Popular posts from this blog

Adding Emoji icons to Rails application

Its very easy to add emoji icons/images to your rails application. It seems complex but its all easy using javascript.The steps can be simplified as shown below:- add the javascript(download jemotion ) include it in your view file(where you want :) to be shown as this -----------------------> thats it....done first you need to add this wonderful js which works really great and nice from home page . We are interested in only the js and emotions folder(containing the smileys/GIF images). once you download just include it in your view file and copy/dump the emotions folder(containing images) to app/assets/images for RAILS 3+. as i did where i want the users to view their comments after they submit their comment. You also need to give a unique id to make  the js understand where it needs to convert your symbols to icons.see below code and hope you will understand how to use it. Keep in mind two thing:- dont forget t...
1 comment
Read more

Using Geocoder to get street name,state,city,country etc in Your Rails app

Recently i implemented Google map for one of the module where User will enter his location/address and other relevant geo-details should get autopopulated.Well,This was posible because of   Geocoder  and by using it you can get every small details such as postalcode,country code,zipcode,street name,state name,state code,latitude,longitude(and more) ready in your hands easily.Its really awesome. I have used to it get all relevant information about the location that the user enter using Geocomplete ,another awesome autocomplete library to get locations. Suppose you have a users table and also few columns such as longitude,latitude,state,postal code,street name,address,country  and want to autopopulate other fields just by using address entered by the user then you are reading the right blog,So its easy,let me show you how. User will enter address using Geocomplete and store that address in address column in users/locations table Then,use Geocoder to fetch other geo...
Post a Comment
Read more

Show image preview on upload -RAILS

i have been using Ruby on Rails (versions 2/3/4) and loved it because its so quick and saves the time to build website that normally require an year. Recently i implemented uploading videos/music/images using paperclip,ffmpeg-paperclip and delayed_paperclip.i wanted to upload multiple images where i can see the uploaded images before submitting.So here is the code using paperclip and jquery where you can preview your uploaded images in a list format + a customised upload button(see below) instead of the traditional browse button for uploading files. i am using bootstrap 3 and FontAwesome(for upload button icon) Description:- In the form,i have input button of type file and added a style to give it a look as shown above which works good and responsively.  In the jquery,it detects for a change in upload button using change event listener and get all the uploaded file and lists it to the  div with id = list using li The code also has validations to show error...
Post a Comment
Read more