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在 Android 开发中使用 Room 时出现如下错误信息java.lang.IllegalStateException: A migration from 6 to 7 was required but not found. Please provide the necessary Migration path via RoomDatabase.Builder.addMigration(Migration ...) or allow for destructive migrations via one of the RoomDatabase.Builder.fallbackToDestructiveMigration* methods.# 解读 java.lang.IllegalStateException 需要从版本 6 到版本 7 的迁移策略但未找到 请通过 RoomDatabase.Builder.addMigration(Migration ...) 提供必要的迁移路径 或者通过 RoomDatabase.Builder.fallbackToDestructiveMigration* 方法之一允许破坏性迁移问题原因使用 Room 将数据库从版本 6 升级到版本 7但没有提供对应的迁移策略处理策略通过 addMigration 方法提供必要的迁移策略推荐privatestaticfinalMigrationMIGRATION_6_7newMigration(6,

{Overridepublicvoidmigrate(NonNullSupportSQLiteDatabasedatabase){...}};MyDatabasemyDatabaseRoom.databaseBuilder(MyApplication.getContext(),MyDatabase.class,DATABASE_NAME).addMigrations(MIGRATION_1_

.addMigrations(MIGRATION_2_

.addMigrations(MIGRATION_3_

.addMigrations(MIGRATION_4_

.addMigrations(MIGRATION_5_

.addMigrations(MIGRATION_6_

.build();通过 fallbackToDestructiveMigration 方法允许破坏性迁移不推荐MyDatabasemyDatabaseRoom.databaseBuilder(MyApplication.getContext(),MyDatabase.class,DATABASE_NAME).fallbackToDestructiveMigration().build();

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