Hi, I have a product with two images and two variants.I update the product - the only change is that I associate one of the product images with one of the variants by: a) The image_id field of the variant is set to the id of the image (6372517251) b) The variants Id field of the image is set to the id of the variant (9033911235) My PUT json is: the response json from the PUT operation is: When I look at the product, it is not updated as expected, there is no image associated with the variant.In this first part, we’ll talk about performance and how to speed up a sluggish Rails app. Like the index of a book, they take up space, but when you go to look up “chimpanzee”, you don’t need to flip through each page to find it.You simply find it in the index and turn to the page it references.Unless you’ve used eager-loading to prepare the database for a query like the one above, Rails is going to perform a query to fetch the comment count for each article.If you have a lot of articles, this is extremely inefficient.In this case, we can cache our product index and specify a condition which invalidates the cache of products.
In this case, there might be the following line in the code .
This in turn speeds up your users’ interaction with the site.
As your application grows and your models and their relationships become more and more complex, one of the biggest sink-holes for performance is the N 1 query.
We need to send the database a memo telling it to optimize itself to be able to look up contacts using their phone number. In Active Record, you do this with a migration: Now, when we look up a contact by its phone number, the database knows exactly where to look to locate that contact and can return it in a fraction of the time.
Caching parts of your application that don’t change often is a great way to speed up a user’s interaction with your website.As a rule of thumb, you should index any field that’s used to look up an object.