If you are creating Lightning components and working with a single record of data, you should be using the Lightning Data Service (LDS) or the force:recordData tag.
And for those of you that have not heard about the LDS, you can think of it as the standard controller for lightning components. It is similar to the standard controller used in Visualforce in that it gets you access to your orgs data, but without the need to write any Apex or SOQL and that is a pretty cool thing because when you don’t have to worry about writing Apex, you also do not have to worry about FLS or Field Level Security and CRUD or Create Access Update and Delete security, which is something you would have to specifically check for in your code if you did not use the Lightning Data Service.
You see I have to tell you that all of you Visualforce developers have been a bit spoiled when it comes to security, b/c in most cases, the pages that you wrote did not have to specifically check for these permissions (even when they used controllers). But, the Lightning Platform works very differently than Visualforce and any Apex code you write does have to do these checks, which involves writing more code.
With the Lightning Data Service, you also get other built-in features like auto-notifications when there are record changes, as well as offline access for Salesforce1.
And if all that was not enough to convince you that Lightning Data Service is something you want to use, here is one more really big reason. Even if you have multiple components using the Lightning Data Service, they are all going to use a single request and deal with a cached response and in terms of performance this is huge.
Even if you have multiple components using the Lightning Data Service, they are all going to use a single request and deal with a cached response
So let’s talk about that a bit more. Let’s say you have two components that are using the force:recordData tag. Each one will make a request for data through the Lightning Data Service Controller, and those requests will be funneled into one single request which is sent to the Salesforce server, such as you see here.
But what is returned is a response that will be stored in a shared data cache and also returned back to the two components that started all this, such as in the diagram below. And this means that not only will those two components be able to retrieve the data faster than two components that were using their own apex controllers
But if a third component that needed that same data were to come along, it would be able to get a cached response almost immediately without even having to make a call to the server. Boom!
So now do you see why you need to be using the Lightning Data Service whenever possible?
If you found this article useful, you might want to checkout my latest course on Pluralsight titled, Lightning Component Development Best Practices, where I talk about the Lightning Data Service and a lot more.