Android 房间自定义更新 @Query 与字符串数组崩溃与“sqlite 语法？错误”

Question

所以我在@Query 中的 UPDATE 查询有问题，它试图更新一个包含 String[] 的列。

转换器：

@TypeConverter
public static String[] fromString(String value) {
    Type listType = new TypeToken<String[]>() {
    }.getType();
    return new Gson().fromJson(value, listType);
}

@TypeConverter
public static String fromArrayList(String[] list) {
    //Type listType = new TypeToken<String[]>() {
    //}.getType();
    Gson gson = new Gson();
    String json = gson.toJson(list);
    return json;
}

道：

@Dao
public interface CharacterDao {

    @Insert(onConflict = OnConflictStrategy.IGNORE)
    long[] insertCharacters(Character... characters);

    @Query("UPDATE characters SET name = :name, episodes = :episodes, createdDate = :createdDate " +
            "WHERE character_id = :character_id")
    void updateCharacter(String character_id, String name, String[] episodes, String createdDate);
}

因此，为了更深入地解释它，我现在正在尝试在我的 Repository.class 中执行的update操作是在insert返回 -1时对用户执行（因此存在冲突）。我还为整个数据库添加了@TypeConverters，虽然我试图将它添加到 dao 和实体等，但它没有解决问题。

因此，在使用适当的参数调用 characterDao.updateCharacter 时会出现问题。当我从方法调用和@query 中删除剧集数组时，它工作得很好，所以 String[] 是这里的问题。

但是，当我使用 @Update 而不是自定义 @Query 时，它工作得很好。但这仍然困扰着我，而且在任何地方都没有答案。

仅供参考插入工作正常。问题仅在于更新

我得到的错误是“语法？错误”

痕迹：

  --------- beginning of crash
2019-05-15 14:29:23.556 20853-21022/pl.com.bubka.characs E/AndroidRuntime: FATAL EXCEPTION: pool-1-thread-1
    Process: pl.com.bubka.characs, PID: 20853
    android.database.sqlite.SQLiteException: near "?": syntax error (Sqlite code 1 SQLITE_ERROR): , while compiling: UPDATE characters SET name = ?, episodes = ?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?, createdDate = ? WHERE character_id = ?, (OS error - 0:Success)
        at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
        at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:948)
        at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:559)
        at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:603)
        at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:63)
        at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
        at android.database.sqlite.SQLiteDatabase.compileStatement(SQLiteDatabase.java:1166)
        at androidx.sqlite.db.framework.FrameworkSQLiteDatabase.compileStatement(FrameworkSQLiteDatabase.java:64)
        at androidx.room.RoomDatabase.compileStatement(RoomDatabase.java:249)
        at pl.com.bubka.characs.database.CharacterDao_Impl.updateCharacter(CharacterDao_Impl.java:465)
        at pl.com.bubka.characs.repositories.CharactersRepository$1.saveCallResult(CharactersRepository.java:50)
        at pl.com.bubka.characs.repositories.CharactersRepository$1.saveCallResult(CharactersRepository.java:39)
        at pl.com.bubka.characs.utils.NetworkBoundResources$3$1.run(NetworkBoundResources.java:69)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
        at java.lang.Thread.run(Thread.java:784)

Answer 1

像这样修改你的 DAO 文件：

@Dao
public interface CharacterDao {

    @Insert(onConflict = OnConflictStrategy.IGNORE)
    long[] insertCharacters(Character... characters);

    @Update
    void update(Character character);

/*By using above Annotation @Update()
  Room Db automatically identifies Entity (in this case Character object)
  from primary key and try to update changed Values for that id*/
}

用法：

Character character = new Character();
character.setId(character_id);// or whatever primary key (mandatory)
character.setName(name); // add all 

character.set...(yourParams); //any other parameters to update
characterDao.update(character); // reference your character_dao

参考： Android Room 文档