Beginning Core Data | Ray Wenderlich

Learn the basics of using Core Data in this beginning series! You’ll learn how to model your data with attributes and relationships; add and update records; and then fetch your data with sorting and filtering options.


This is a companion discussion topic for the original entry at https://www.raywenderlich.com/7104-beginning-core-data

This video tutorial is irritating is just coding but not explain why you are using each thing just says " replace te code with the fallowing" in this video tutorial you will not lear nothing.
You are not using the pointer to show when you are explaining where you are explaining.
I did not continue with the video tutorials You are typing but you are not understanding what you are doing.

You have to create video tutorials with steps:

  • create entity…
  • create …
    always with small projects
    also you can put the images or explanations while you are typing and not just in the begging of each video. to have a reference of the explanation and the code.
    like a list of steps that you can remember easier than just typing.
    I thought it was goin to be a better video tutorials in Ray Wenderlich.

Thanks for the heads up. We’ll keep your feedback in mind when we produce future courses. Thanks!

I think it is because you just watched the latest version. I watched each version and it explained each line pretty well. I think it would be good if you could just watch the latest version and everything be re explained without having to watch previous versions for details. All in all as long as you watch all versions, it does explain the details.

I believe it was a great tutorial but had to watch it twice in which at first time, I was like… oh wooooow… what is happening… too much to grasp… could not understand it… but keep on playing till last just to be familiar with all terminology…
Later, I was trying to integrate CoreData in my small Calendar project, then I had to visit couple of other videos and grope couple of basic concepts for imagination… Like

  1. Imagine Entity as table as we used to learn in Database courses… columns as property and rows as stored data…
  2. Context as temporary scratch pad on which u can load table and rows by querying database and relationship is just Common column kind of thing…

After grasping it… I watched tutorial again… and boom… I could relate everything very clearly… Even I noticed that you said to relate it with Database tables for imagination… But I don’t know if I missed it first time…

I think, this tutorial could be better If you we would have started with some drawing or images of tables, columns and rows for imagination as I mentioned two points earlier… Hope that would help…

That’s definitely one approach, but the thing about Core Data is that its an object persistence framework as opposed to a database driven system. In some cases, you can use a database, but you can also use an XML file or even your own storage medium.

That said, there is definite value in introducing the metaphor to help make it “click” but I’d avoid using it as the only metaphor. In any case, thanks for your feedback!

This is good content, very interesting. However, I am wondering what kind of technology was used before Core Data, when Objective C was the main language.

Hi Matt, Back in the Objective-C days we used Core Data. It was the same API (albeit with some changes in the last few years), but the main concepts haven’t changed in that time. The code in Objective-C looks quite similar with lots of brackets.

Would be fabulous if you guys could please update this course for Swift 5.x, iOS 13.x, Xcode 11.x.

WOW THAT WAS QUICK!!! I just did a search and the new course was released yesterday. yay!!

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Hi Brian, I have a general question if you dont mind -

if you have two entities A,B and B is related to A such that A has one to many B’s. If you query A you automatically get all the related B’s in an ordered set. Suppose this set would contain 100,000 records of B. Would querying of A bring all the related B’s in one go? Can you use a NSFetchedResultsController to control the resulting B’s for display in a table ? What would the best way of extracting the resulting B records for displaying in a table view be ?

Thanks

It’s been a long time since I worked with Core Data (although I’m starting to use it again on a personal project) but I believe Core Data works on a lazy loading. This means it will only load the object until you actually need to use it. It’s been awhile so Apple Documentation is your best resource.

@richardwau Please check out the updated version of the course when you get a chance:

I hope it helps!