为什么在将核心数据属性从Integer 16更改为String时看到此错误？

Question

我有一个Core数据模型，其中一个属性当前设置为Integer 16。我现在想要更改属性名称和类型，但保留当前数据。我已经对名称更改进行了排序，并且运行起来没有任何问题。

在尝试更改数据类型时，我得到了以下非常长的错误，我可以做些什么来解决它？

2012-07-10 19:33:06.298 Medicine Tracker[5170:707] Unresolved error Error Domain=NSCocoaErrorDomain Code=134140 "The operation couldn’t be completed. (Cocoa error 134140.)" UserInfo=0x2ae140 {reason=Can't find or automatically infer mapping model for migration, destinationModel=(<NSManagedObjectModel: 0xf694e20>) isEditable 0, entities {
Log = "(<NSEntityDescription: 0xf6947b0>) name Log, managedObjectClassName Log, renamingIdentifier Log, isAbstract 0, superentity name (null), properties {\n    date = \"(<NSAttributeDescription: 0xf6941d0>), name date, isOptional 1, isTransient 0, entity Log, renamingIdentifier date, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 900 , attributeValueClassName NSDate, defaultValue (null)\";\n    medicine = \"(<NSRelationshipDescription: 0xf694410>), name medicine, isOptional 1, isTransient 0, entity Log, renamingIdentifier medicine, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, destination entity Medicine, inverseRelationship logs, minCount 1, maxCount 1, isOrdered 0, deleteRule 1\";\n    note = \"(<NSAttributeDescription: 0xf694220>), name note, isOptional 1, isTransient 0, entity Log, renamingIdentifier note, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\";\n}, subentities (null), userInfo {\n}, versionHashModifier (null)";
Medicine = "(<NSEntityDescription: 0xf694810>) name Medicine, managedObjectClassName Medicine, renamingIdentifier Medicine, isAbstract 0, superentity name (null), properties {\n    active = \"(<NSAttributeDescription: 0xf694270>), name active, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier active, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 800 , attributeValueClassName NSNumber, defaultValue (null)\";\n    dose = \"(<NSAttributeDescription: 0xf6942c0>), name dose, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier amountToTake, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\";\n    hoursBetween = \"(<NSAttributeDescription: 0xf694310>), name hoursBetween, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier hoursBetween, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 100 , attributeValueClassName NSNumber, defaultValue 0\";\n    logs = \"(<NSRelationshipDescription: 0xf694470>), name logs, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier logs, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, destination entity Log, inverseRelationship medicine, minCount 0, maxCount 0, isOrdered 0, deleteRule 1\";\n    name = \"(<NSAttributeDescription: 0xf694360>), name name, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier name, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n    \\\"com.apple.syncservices.Syncable\\\" = NO;\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\";\n}, subentities (null), userInfo {\n    \"com.apple.syncservices.Syncable\" = NO;\n}, versionHashModifier (null)"; }, fetch request templates { }, sourceModel=(<NSManagedObjectModel: 0x2adbb0>) isEditable 1, entities {
Log = "(<NSEntityDescription: 0x2ac700>) name Log, managedObjectClassName Log, renamingIdentifier Log, isAbstract 0, superentity name (null), properties {\n    date = \"(<NSAttributeDescription: 0x294ac0>), name date, isOptional 1, isTransient 0, entity Log, renamingIdentifier date, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 900 , attributeValueClassName NSDate, defaultValue (null)\";\n    medicine = \"(<NSRelationshipDescription: 0x294a60>), name medicine, isOptional 1, isTransient 0, entity Log, renamingIdentifier medicine, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, destination entity Medicine, inverseRelationship logs, minCount 1, maxCount 1, isOrdered 0, deleteRule 1\";\n    note = \"(<NSAttributeDescription: 0x2ac810>), name note, isOptional 1, isTransient 0, entity Log, renamingIdentifier note, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\";\n}, subentities {\n}, userInfo {\n}, versionHashModifier (null)";
Medicine = "(<NSEntityDescription: 0x294b10>) name Medicine, managedObjectClassName Medicine, renamingIdentifier Medicine, isAbstract 0, superentity name (null), properties {\n    active = \"(<NSAttributeDescription: 0x2adaa0>), name active, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier active, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 800 , attributeValueClassName NSNumber, defaultValue (null)\";\n    dose = \"(<NSAttributeDescription: 0x2adaf0>), name dose, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier amountToTake, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 100 , attributeValueClassName NSNumber, defaultValue 0\";\n    hoursBetween = \"(<NSAttributeDescription: 0x2adb40>), name hoursBetween, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier hoursBetween, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, attributeType 100 , attributeValueClassName NSNumber, defaultValue 0\";\n    logs = \"(<NSRelationshipDescription: 0x2ada40>), name logs, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier logs, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n}, destination entity Log, inverseRelationship medicine, minCount 0, maxCount 0, isOrdered 0, deleteRule 1\";\n    name = \"(<NSAttributeDescription: 0x2ad9f0>), name name, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier name, validation predicates (\\n), warnings (\\n), versionHashModifier (null)\\n userInfo {\\n    \\\"com.apple.syncservices.Syncable\\\" = NO;\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\";\n}, subentities {\n}, userInfo {\n    \"com.apple.syncservices.Syncable\" = NO;\n}, versionHashModifier (null)"; }, fetch request templates { }, NSUnderlyingError=0x2b0140 "The operation couldn’t be completed. (Cocoa error 134190.)"}, {
NSUnderlyingError = "Error Domain=NSCocoaErrorDomain Code=134190 \"The operation couldn\U2019t be completed. (Cocoa error 134190.)\" UserInfo=0x2b0160 {reason=Source and destination attribute types are incompatible, entity=Medicine, property=dose}";
destinationModel = "(<NSManagedObjectModel: 0xf694e20>) isEditable 0, entities {\n    Log = \"(<NSEntityDescription: 0xf6947b0>) name Log, managedObjectClassName Log, renamingIdentifier Log, isAbstract 0, superentity name (null), properties {\\n    date = \\\"(<NSAttributeDescription: 0xf6941d0>), name date, isOptional 1, isTransient 0, entity Log, renamingIdentifier date, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 900 , attributeValueClassName NSDate, defaultValue (null)\\\";\\n    medicine = \\\"(<NSRelationshipDescription: 0xf694410>), name medicine, isOptional 1, isTransient 0, entity Log, renamingIdentifier medicine, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, destination entity Medicine, inverseRelationship logs, minCount 1, maxCount 1, isOrdered 0, deleteRule 1\\\";\\n    note = \\\"(<NSAttributeDescription: 0xf694220>), name note, isOptional 1, isTransient 0, entity Log, renamingIdentifier note, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\\\";\\n}, subentities (null), userInfo {\\n}, versionHashModifier (null)\";\n    Medicine = \"(<NSEntityDescription: 0xf694810>) name Medicine, managedObjectClassName Medicine, renamingIdentifier Medicine, isAbstract 0, superentity name (null), properties {\\n    active = \\\"(<NSAttributeDescription: 0xf694270>), name active, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier active, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 800 , attributeValueClassName NSNumber, defaultValue (null)\\\";\\n    dose = \\\"(<NSAttributeDescription: 0xf6942c0>), name dose, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier amountToTake, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\\\";\\n    hoursBetween = \\\"(<NSAttributeDescription: 0xf694310>), name hoursBetween, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier hoursBetween, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 100 , attributeValueClassName NSNumber, defaultValue 0\\\";\\n    logs = \\\"(<NSRelationshipDescription: 0xf694470>), name logs, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier logs, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, destination entity Log, inverseRelationship medicine, minCount 0, maxCount 0, isOrdered 0, deleteRule 1\\\";\\n    name = \\\"(<NSAttributeDescription: 0xf694360>), name name, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier name, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n    \\\\\\\"com.apple.syncservices.Syncable\\\\\\\" = NO;\\\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\\\";\\n}, subentities (null), userInfo {\\n    \\\"com.apple.syncservices.Syncable\\\" = NO;\\n}, versionHashModifier (null)\";\n}, fetch request templates {\n}";
reason = "Can't find or automatically infer mapping model for migration";
sourceModel = "(<NSManagedObjectModel: 0x2adbb0>) isEditable 1, entities {\n    Log = \"(<NSEntityDescription: 0x2ac700>) name Log, managedObjectClassName Log, renamingIdentifier Log, isAbstract 0, superentity name (null), properties {\\n    date = \\\"(<NSAttributeDescription: 0x294ac0>), name date, isOptional 1, isTransient 0, entity Log, renamingIdentifier date, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 900 , attributeValueClassName NSDate, defaultValue (null)\\\";\\n    medicine = \\\"(<NSRelationshipDescription: 0x294a60>), name medicine, isOptional 1, isTransient 0, entity Log, renamingIdentifier medicine, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, destination entity Medicine, inverseRelationship logs, minCount 1, maxCount 1, isOrdered 0, deleteRule 1\\\";\\n    note = \\\"(<NSAttributeDescription: 0x2ac810>), name note, isOptional 1, isTransient 0, entity Log, renamingIdentifier note, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\\\";\\n}, subentities {\\n}, userInfo {\\n}, versionHashModifier (null)\";\n    Medicine = \"(<NSEntityDescription: 0x294b10>) name Medicine, managedObjectClassName Medicine, renamingIdentifier Medicine, isAbstract 0, superentity name (null), properties {\\n    active = \\\"(<NSAttributeDescription: 0x2adaa0>), name active, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier active, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 800 , attributeValueClassName NSNumber, defaultValue (null)\\\";\\n    dose = \\\"(<NSAttributeDescription: 0x2adaf0>), name dose, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier amountToTake, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 100 , attributeValueClassName NSNumber, defaultValue 0\\\";\\n    hoursBetween = \\\"(<NSAttributeDescription: 0x2adb40>), name hoursBetween, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier hoursBetween, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, attributeType 100 , attributeValueClassName NSNumber, defaultValue 0\\\";\\n    logs = \\\"(<NSRelationshipDescription: 0x2ada40>), name logs, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier logs, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n}, destination entity Log, inverseRelationship medicine, minCount 0, maxCount 0, isOrdered 0, deleteRule 1\\\";\\n    name = \\\"(<NSAttributeDescription: 0x2ad9f0>), name name, isOptional 1, isTransient 0, entity Medicine, renamingIdentifier name, validation predicates (\\\\n), warnings (\\\\n), versionHashModifier (null)\\\\n userInfo {\\\\n    \\\\\\\"com.apple.syncservices.Syncable\\\\\\\" = NO;\\\\n}, attributeType 700 , attributeValueClassName NSString, defaultValue (null)\\\";\\n}, subentities {\\n}, userInfo {\\n    \\\"com.apple.syncservices.Syncable\\\" = NO;\\n}, versionHashModifier (null)\";\n}, fetch request templates {\n}"; }

Answer 1

您正在将现有的SQL或其他持久性存储与新模式一起交给Core Data，新模式说明相关属性具有特定的名称和类型。然后，当Core Data查看存储时，它会发现存储的格式不符合当前模式。这会导致抛出您所看到的错误。

如果你还没有发布应用程序，那么只需删除你当前的存储空间(如果你在谈论iOS，就删除该应用程序)，然后重新启动。一切都会好起来的。

如果您确实需要执行迁移-例如，如果旧的模式已经部署-那么您显然需要考虑迁移。

粗略浏览一下，this看起来像是不错的信息。

最终，您将在项目中获得两个版本的模式，并为Core Data提供足够的信息来在它们之间进行映射。如果你只是在谈论字段重命名，那么你可以仅仅通过模式来实现(当你选择了一个属性并点击查看数据模型检查器，最右边的标签时，查看Xcode右侧实用工具窗格中“版本控制”下的“Renaming ID”字段)，但是我不确定这是否可以强制类型。如果不能，那么您将另外得到一个映射模型，这是另一个可以在Xcode中编辑的图形化东西，它肯定可以强制执行。

Answer 2

如果你遇到这样的问题，尝试在另一台你从未使用过的设备的模拟器中运行该应用程序，看看它是否对你有帮助(例如，iPhone SE而不是iPhone 7)。如果是这样，那么删除损坏的文件夹应该会有所帮助。打开终端并运行以下命令：

sudo rm -rf ~/Library/Developer/CoreSimulator/Devices

为了移除可能被破坏的模拟器数据，

sudo rm -rf ~/Library/Developer/XCode/DerivedData/

若要删除应用程序的数据，请执行以下操作。

它解决了我的问题。希望它能帮上忙！

Answer 3

我在Xcode 10和Swift 4.2中也遇到了同样的问题。

当我更改了CoreData的实体String to Int16后，我从设备上卸载了应用程序，然后重新安装它。

这对我很管用。