Defining database columns, but not using the CodingKeys enum

[hell001]

What did you do?

I have an API that has a title key, but in my code I'd like to have it named name. I create a CodingKeys enum so that my app can properly read the JSON and also use the variable name I choose. See a truncated version of the class below:

class A: Codable, Identifiable {
    var name: String
    
    enum CodingKeys: String, CodingKey {
        case name = "title"
    }
}

As per Define Record Requests, I created a Columns enum as follows below. However, instead of using the CodingKeys value CodingKeys.name, I used the String of the variable name itself, which is what I desire the column name to be.

extension A: FetchableRecord, MutablePersistableRecord {
    enum Columns {
        static let name = Column("name")
    }
}

So to clarify, I still would like to use CodingKeys to go from title from API response to name in Swift code, but still want to use name as the GRDB column name, and not take it from CodingKeys, which would be title.

For extra clarification, the errors occur on my aInstance.insert(db) calls. table a has no column named title

What did you expect to happen?

The column name is name.

What happened instead?

The column name is title.

Environment

GRDB flavor(s): GRDB
GRDB version:
Installation method: SPM
Xcode version:
Swift version: 5
Platform(s) running GRDB: iOS
macOS version running Xcode: 11.0

[groue]

Hello @hell001,

Please show how you define this name/title Column value.

[hell001]

Hello @groue,

Assuming you are not referring to any of the code in the original post,

class A: Codable, Identifiable {
    var name: String

    enum CodingKeys: String, CodingKey {
        case name = "title"
    }
}

[groue]

Assuming you are not referring to any of the code in the original post,

Whenever someone asks for support, I always refer to the actual code that creates the actual problem. Everything else is just noise.

Your answer does not contain any Column value. However you explicitly ask that the name property is encoded in a title JSON key or database column.

I'm not sure I can help with the available information. If you want help from this discussion, please provide a Minimal, Reproducible Example.

[hell001]

does the following code from my original post not include a column value? (quoted below for your convenience)

//1
enum Columns {
        static let name = Column("name")
}

//2
enum Columns: String, ColumnExpression {
        case name
}

[hell001]

@groue This is definitely putting me on the right path. After implementing this protocol function encode the database is successfully written to, and I can confirm correctly as when I open the SQLite file, everything looks as intended as far as column names. My next question is, is there some equivalent decoding function that needs to be implemented? After expanding on the project a bit, I seem to get an error of:

Fatal error: 'try!' expression unexpectedly raised an error: column not found: "title" - row: [id:"1" name:"Name"], sql: `SELECT "a".* FROM "a" JOIN "ab" ON ("ab"."aId" = "a"."id") AND ("ab"."bId" = ?)`, arguments: ["1"]

Why is GRDB trying to select title? I bring in another class B because if I were to simply call A.fetchAll(db), this works with no problem, which confuses me. I Ctrl+F the entire project and the only mention of title is in CodingKeys.

To clarify, I am receiving the above error when calling b.aList.fetchAll(db)

See all code below:

class A: Codable, Identifiable {
    var id: String
    var name: String
    
    enum CodingKeys: String, CodingKey {
        case id
        case name = "title"
    }
}

extension A: FetchableRecord, MutablePersistableRecord {}

extension A {
    static let ab = hasMany(AB.self)
    static let bList = hasMany(B, through: ab, using: AB.b)
}

extension A {
    var bList: QueryInterfaceRequest<B> {
        request(for: A.bList)
    }
}

extension A: EncodableRecord {
    func encode(to container: inout PersistenceContainer) {
        container["name"] = name
    }
}

class B: Codable, Identifiable {
    var id: String
}

extension B: FetchableRecord, MutablePersistableRecord {}

extension B {
    static let ab = hasMany(AB.self)
    static let aList = hasMany(A.self, through: ab, using: AB.a)
}

extension B {
    var aList: QueryInterfaceRequest<A> {
        request(for: B.aList)
    }
}

class AB: Codable {
    var aId: String
    var bId: String
    
    init(aId: String, bId: String) {
        self.aId = aId
        self.bId = bId
    }
}

extension AB: FetchableRecord, PersistableRecord {}

extension AB {
    static let a = belongsTo(A.self)
    static let b = belongsTo(B.self)
}

Let me know if I should turn this into an issue post. I figured I was missing something tho

[groue]

Oh, so you did not read a single line of the doc, and you expect me to digest it for you. This is a very wrong expectation.

Records

[hell001]

@groue If I “did not read a single line of the doc” how would I know what this sharp tool even is? Let’s not exaggerate. What I am saying is that even after reading the docs, I am failing to see the part that addresses my previous comment. And as I stated I could simply be missing it or even misinterpreting when going through, in which case I ask for help. After reading the documentation and trying to implement something myself, and after that still I cannot do it, what else should I do that isn’t asking for help with a very detailed question, providing “a Minimal, Reproducible Example.“ ?

[hell001]

@groue Following up...

[groue]

@hell001, you have recently damaged two other discussions, #1055 and #1049. I have repaired the one that can raise the interest of other users. Please do not do that again.