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Bypassing the Migration

Simplest way to bypass the Migration​

We can drop the database each time we make a change in the schema using deleteRealmIfMigrationNeeded. This is a quick way to bypass the migration while in development but we should never ship an app using this.

Add the RealmSwift import​

GoodHabitsRealmAppApp.swift
import RealmSwift

This will create a problem, as both SwiftUI and RealmSwift have an App type. To fix this, we'll add SwiftUI to our app like:

GoodHabitsRealmAppApp.swift
struct GoodHabitsRealmAppApp: SwiftUI.App {

Get default config and set deleteRealmIfMigrationNeeded​

Here we just change the config for DEBUG builds. This way we avoid shipping this code.

GoodHabitsRealmAppApp.swift
// ...
struct GoodHabitsRealmAppApp: SwiftUI.App {
    var config = Realm.Configuration.defaultConfiguration

    init() {
        #if DEBUG
        config.deleteRealmIfMigrationNeeded = true
        #endif
    }

    // ...
}

Complete listing​

Our new GoodHabitsRealmAppApp look like this. Now we can change our schema without getting errors, but we'll lose any changes in the database.

GoodHabitsRealmAppApp.swift
import SwiftUI
import RealmSwift

@main
struct GoodHabitsRealmAppApp: SwiftUI.App {
    var config = Realm.Configuration.defaultConfiguration

    init() {
        #if DEBUG
        config.deleteRealmIfMigrationNeeded = true
        #endif
    }

    var body: some Scene {
        WindowGroup {
            MainView()
                .environment(\.realmConfiguration, config)
        }
    }
}