[SeSAC] 20220822_TIL (Realm)

1.Swift DataBase - Realm

1.임포트

import RealmSwift

 

2.스키마 정의(테이블 생성)

// LocalOnlyQsTask is the Task model for this QuickStart
class LocalOnlyQsTask: Object {
    @Persisted var name: String = ""
    @Persisted var owner: String?
    @Persisted var status: String = ""
    
    
    //초기화
    convenience init(name: String) {
        self.init()
        self.name = name
    }
}

-한번 빌드된 앱에서 위 스키마의 내용이 바뀌게 되면 마이그레이션이 필요하다

-앱 삭제 후 다시 빌드

 

3.위치 가져오기

// Open the local-only default realm
let localRealm = try! Realm()

 

4.CRUD(Create(생성), Read(읽기), Update(갱신), Delete(삭제))

// Add some tasks
// 저장
let task = LocalOnlyQsTask(name: "Do laundry")
try! localRealm.write {
    localRealm.add(task)
}

// Get all tasks in the realm
let tasks = localRealm.objects(LocalOnlyQsTask.self)

// You can also filter a collection
let tasksThatBeginWithA = tasks.where {
    $0.name.starts(with: "A")
}
print("A list of all tasks that begin with A: \(tasksThatBeginWithA)")

// All modifications to a realm must happen in a write block.
let taskToUpdate = tasks[0]
try! localRealm.write {
    taskToUpdate.status = "InProgress"
}

// All modifications to a realm must happen in a write block.
let taskToDelete = tasks[0]
try! localRealm.write {
    // Delete the LocalOnlyQsTask.
    localRealm.delete(taskToDelete)
}

 

5.모델 정의

//@Persisted var value: <Type>

//@Persisted var value: Data()
//@Persisted var value: Date()

//ex.
//Dog - 테이블 이름
//@Persisted - 컬럼
class Dog: Object {
    @Persisted var name = ""
    @Persisted var currentCity = ""
    @Persisted var citiesVisited: MutableSet<String>
    @Persisted var title: String
    
    //PK 지정 - 중복X 필수값 => ObjectID
    @Persisted(primaryKey: true) var objectID: ObjectID
     
}

 

6.PK지정

class Project: Object {
    @Persisted(primaryKey: true) var id = 0
    @Persisted var name = ""
}

 

7.스키마 경로 확인

// Get on-disk location of the default Realm
let realm = try! Realm()
print("Realm is located at:", realm.configuration.fileURL!)

-단순 확인용으로 viewDidLoad에 작성하여 앱 실행과 동시에 경로가 표시되도록 할 수 있다.

 

결과