尽管添加了 GreenDao "PRIMARY KEY must be unique" 错误 "myEntity.addIdProperty().autoIncreament()"

Question

我是 GreenDAO 的新手。这是我的发电机 class

public class FlashCardGenerator {
    public static void main(String args[]) throws Exception {
        Schema schema = new Schema(1, "com.flashcard.model");

        Entity lesson = schema.addEntity("Lesson");
        lesson.addIdProperty().autoincrement();
        lesson.addStringProperty("LessonName");
        lesson.addStringProperty("ShortDes");
        lesson.addStringProperty("LongDes");

        Entity card = schema.addEntity("Card");
        card.addIdProperty().autoincrement();
        card.addStringProperty("SourceText");
        card.addStringProperty("TargetText");
        card.addByteArrayProperty("Image");

        Property lessonID = card.addLongProperty("lessonID").getProperty();
        card.addToOne(lesson, lessonID);
        ToMany lessonToCard = lesson.addToMany(card, lessonID);
        lessonToCard.setName("cards");

        new DaoGenerator().generateAll(schema,"../app/src/main/java");
    }
}

尽管我将 id 列添加到 "lesson" 并使其自动增加。当我使用此代码时

DaoMaster.DevOpenHelper helper = new DaoMaster.DevOpenHelper(this, "flashcard-db", null);
SQLiteDatabase db = helper.getWritableDatabase();
DaoMaster daoMaster = new DaoMaster(db);DaoSession daoSession = daoMaster.newSession();
LessonDao lessonDao = daoSession.getLessonDao();
Lesson lesson = new Lesson( 1L,"Demo L1", "Nothing", "nothing");
long l = lessonDao.insert(lesson);

if (l > 0) {
   Toast.makeText(getApplicationContext(), "Success", Toast.LENGTH_SHORT);
} else {
    Toast.makeText(getApplicationContext(), "Fail! OMG", Toast.LENGTH_SHORT);
}

第一次运行项目，记录插入成功，第二次运行项目，出现"PRIMARY KEY must be unique"错误。这是暴力主键时的常见错误。但是我也设置了AutoIncreament？可能是因为我将Id设置为1L？ Generated-class不建议修改，Lesson的所有构造函数都是有"Id"param.

Answer 1

好的，很快，在 GreenDao support 上进行了一些搜索后，我找到了解决方案，只需将 ID 参数设置为 NULL，而不是任何 "long number"。成功了。遇到这样的事情后，我会把post留给任何人

插入代码为：

Lesson lesson = new Lesson( null ,"Demo L1", "Nothing", "nothing");
        long l = lessonDao.insert(lesson);

尽管添加了 GreenDao "PRIMARY KEY must be unique" 错误 "myEntity.addIdProperty().autoIncreament()"

GreenDao "PRIMARY KEY must be unique" error happen despite of added "myEntity.addIdProperty().autoIncreament()"

android

unique

primary-key

greendao