Data not saving to entities #141

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adam · 2025-12-29T18:23:29+01:00

adam commented

2025-12-29 18:23:29 +01:00

Originally created by @martheli on GitHub (May 25, 2017).

My code runs without error but when I try to print out the entity I receive the following print:

success()
[<Person: 0x600000088ac0> (entity: Person; id: 0xd000000000040000 <x-coredata://71CEC961-C7C3-4466-BD1B-DA19FA909453/Person/p1> ; data: <fault>)]

My code is simple and pretty much right from the readme but it looks like nothing it being added.

CoreStore.perform(
            asynchronous: { (transaction) -> Void in
                let person = transaction.create(Into<Person>())
                person.name = "John Smith"
                person.job = "Dentist"  },

            completion: { (result) -> Void in
                switch result {

                case .success: print(result)
                    
                case .failure(let error): print(error)
                    
                }
            let people = CoreStore.fetchAll(From<Person>())
            print (people!)

Originally created by @martheli on GitHub (May 25, 2017). My code runs without error but when I try to print out the entity I receive the following print: ``` success() [<Person: 0x600000088ac0> (entity: Person; id: 0xd000000000040000 <x-coredata://71CEC961-C7C3-4466-BD1B-DA19FA909453/Person/p1> ; data: <fault>)] ``` My code is simple and pretty much right from the readme but it looks like nothing it being added. ``` CoreStore.perform( asynchronous: { (transaction) -> Void in let person = transaction.create(Into<Person>()) person.name = "John Smith" person.job = "Dentist" }, completion: { (result) -> Void in switch result { case .success: print(result) case .failure(let error): print(error) } let people = CoreStore.fetchAll(From<Person>()) print (people!) ```

adam added the question label 2025-12-29 18:23:29 +01:00

adam closed this issue

2025-12-29 18:23:29 +01:00

adam commented

2025-12-29 18:23:30 +01:00

@JohnEstropia commented on GitHub (May 25, 2017):

Did you already add a store using addStorage()?

CoreStore.addStorage(
    SQLiteStore(fileName: "MyStore.sqlite"),
    completion: { (result) -> Void in
        // ...
    }
)

(See the Setting-up section on the README file)

@JohnEstropia commented on GitHub (May 25, 2017): Did you already add a store using `addStorage()`? ```swift CoreStore.addStorage( SQLiteStore(fileName: "MyStore.sqlite"), completion: { (result) -> Void in // ... } ) ``` (See the [Setting-up](https://github.com/JohnEstropia/CoreStore#setting-up) section on the README file)

adam commented

2025-12-29 18:23:30 +01:00

@martheli commented on GitHub (May 25, 2017):

Yes I have this above:

try CoreStore.addStorageAndWait()

catch
{
print(error)
}

@martheli commented on GitHub (May 25, 2017): Yes I have this above: ``` try CoreStore.addStorageAndWait() catch { print(error) } ```

adam commented

2025-12-29 18:23:30 +01:00

@JohnEstropia commented on GitHub (May 25, 2017):

@martheli Sorry, I just realized you were fetching the object right after calling an asynchronous transaction. perform(asynchronous:...) executes on a background thread, so the object will not be created yet right after the call. You can try fetching inside the completion closure instead:

CoreStore.perform(
            asynchronous: { (transaction) -> Void in
                let person = transaction.create(Into<Person>())
                person.name = "John Smith"
                person.job = "Dentist"  },

            completion: { (result) -> Void in
                switch result {

                case .success:
                    let people = CoreStore.fetchAll(From<Person>())
                    print (people!)
                    
                case .failure(let error): print(error)
                    
                }

@JohnEstropia commented on GitHub (May 25, 2017): @martheli Sorry, I just realized you were fetching the object right after calling an asynchronous transaction. `perform(asynchronous:...)` executes on a background thread, so the object will not be created yet right after the call. You can try fetching inside the `completion` closure instead: ```swift CoreStore.perform( asynchronous: { (transaction) -> Void in let person = transaction.create(Into<Person>()) person.name = "John Smith" person.job = "Dentist" }, completion: { (result) -> Void in switch result { case .success: let people = CoreStore.fetchAll(From<Person>()) print (people!) case .failure(let error): print(error) } ```

adam commented

2025-12-29 18:23:30 +01:00

@martheli commented on GitHub (May 26, 2017):

I moved it inside the completion and the output is the same; no new values.

@martheli commented on GitHub (May 26, 2017): I moved it inside the completion and the output is the same; no new values.

adam commented

2025-12-29 18:23:31 +01:00

@JohnEstropia commented on GitHub (May 26, 2017):

@martheli Can you show your console log?

@JohnEstropia commented on GitHub (May 26, 2017): @martheli Can you show your console log?

adam commented

2025-12-29 18:23:31 +01:00

@martheli commented on GitHub (May 26, 2017):

Output is:

[<Person: 0x600000281680> (entity: Person; id: 0xd000000000040000 <x-coredata://091EEDA4-1652-4D5B-AEA0-110672DEBB1A/Person/p1> ; data: <fault>)]

@martheli commented on GitHub (May 26, 2017): Output is: `[<Person: 0x600000281680> (entity: Person; id: 0xd000000000040000 <x-coredata://091EEDA4-1652-4D5B-AEA0-110672DEBB1A/Person/p1> ; data: <fault>)]`

adam commented

2025-12-29 18:23:31 +01:00

@JohnEstropia commented on GitHub (May 26, 2017):

That looks like the array contents and the Person objects is in it, so I think there is no problem. You can try to print the person's name and job:

print(people![0].name)
print(people![0].job)

@JohnEstropia commented on GitHub (May 26, 2017): That looks like the array contents and the Person objects is in it, so I think there is no problem. You can try to print the person's name and job: ```swift print(people![0].name) print(people![0].job) ```

adam commented

2025-12-29 18:23:31 +01:00

@martheli commented on GitHub (May 26, 2017):

If people is an array, why can't I just print out the array like "print(people)" to list all the values stored in the entity?

@martheli commented on GitHub (May 26, 2017): If people is an array, why can't I just print out the array like "print(people)" to list all the values stored in the entity?

adam commented

2025-12-29 18:23:32 +01:00

@JohnEstropia commented on GitHub (May 26, 2017):

Because Core Data has something called faulting.
Basically all fetched objects's values would only be loaded in memory after the first value is accessed. You can see this behavior if you do this:

print(people!)
print(people![0].name)
print(people!)

You'll notice the last print will print the values because name was accessed on the second print

@JohnEstropia commented on GitHub (May 26, 2017): Because Core Data has something called [faulting](https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/CoreData/FaultingandUniquing.html). Basically all fetched objects's values would only be loaded in memory after the first value is accessed. You can see this behavior if you do this: ```swift print(people!) print(people![0].name) print(people!) ``` You'll notice the last `print` will print the values because `name` was accessed on the second `print`

adam referenced this issue

2025-12-29 18:27:09 +01:00

[PR #141] [CLOSED] [Importing] Convert `shouldUpdate(from:in:)` method to an instance method. #466

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Reference: starred/CoreStore-JohnEstropia#141