Question

我有两张桌子。一个使用主键，另一个使用外键到第一个表。

我尝试将项目添加到第一个项目，然后将项目添加到第二个项目。

我的片段代码：

            long phoneNewId = phoneDal.addItem(newPhone);
            if ( phoneNewId != 0) {
                String comment = ((EditText)rootView.findViewById(R.id.comment_text)).getText().toString();
                commentDal.addItem(phoneNewId, comment);
            }

PhoneDal：

public class PhoneDal extends SQLiteOpenHelper {

    // Database Version
    private static final int DATABASE_VERSION = 1;
    // Database Name
    private static final String DATABASE_NAME = Constants.DB_NAME;

    public static final String BLOCKED_PHONES_TABLE = "BLOCKED_PHONES_TABLE";

    public PhoneDal(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        // SQL statement to create book table

        String CREATE_BLOCKED_PHONES_TABLE =
                "CREATE TABLE "+ BLOCKED_PHONES_TABLE +
                        " ( "+ KEY_ID+" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL  DEFAULT 1, "
                        + KEY_PHONE+" TEXT, "
                             + KEY_IS_BLOCKED+" BIT )";

        db.execSQL(CREATE_BLOCKED_PHONES_TABLE);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        if (newVersion > oldVersion) {
            Log.w("MyAppTag", "Updating database from version " + oldVersion
                    + " to " + newVersion + " .Existing data will be lost.");
            // Drop older books table if existed
            db.execSQL("DROP TABLE IF EXISTS " + BLOCKED_PHONES_TABLE);

            // create fresh books table
            this.onCreate(db);
        }

    }



    private static final String KEY_ID = "id";
    private static final String KEY_PHONE = "KEY_PHONE";
    private static final String KEY_IS_BLOCKED = "KEY_IS_BLOCKED";

    public long addItem(Phone phone) {
        Log.d(Constants.LOGGER_TAG, "add saved-offer");
        // 1. get reference to writable DB
        SQLiteDatabase db = this.getWritableDatabase();

        // 2. create ContentValues to add key "column"/value
        ContentValues values = new ContentValues();
        //values.put(KEY_ID, phone.id);
        values.put(KEY_PHONE, phone.phone);
        values.put(KEY_IS_BLOCKED, phone.isBlocked);

        // 3. insert
        long newRowId =
                db.insertWithOnConflict(BLOCKED_PHONES_TABLE, KEY_ID,
                values, SQLiteDatabase.CONFLICT_REPLACE);

        // 4. close
        db.close();
        return newRowId;
    }

CommentDal：

public class CommentDal extends SQLiteOpenHelper {

    // Database Version
    private static final int DATABASE_VERSION = 1;
    // Database Name
    private static final String DATABASE_NAME = Constants.DB_NAME;

    private static final String COMMENTS_TABLE = "COMMENTS_TABLE";

    public CommentDal(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        // SQL statement to create book table

        String CREATE_COMMENTS_TABLE =
                "CREATE TABLE " + COMMENTS_TABLE +
                        " ( "+ KEY_ID+" INTEGER, "
                             + KEY_COMMENT_TEXT+" TEXT "
                             + "FOREIGN KEY("+KEY_ID+") REFERENCES "+PhoneDal.BLOCKED_PHONES_TABLE+"("+KEY_ID+"))";

        db.execSQL(CREATE_COMMENTS_TABLE);

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        if (newVersion > oldVersion) {
            Log.w("MyAppTag", "Updating database from version " + oldVersion
                    + " to " + newVersion + " .Existing data will be lost.");
            // Drop older books table if existed
            db.execSQL("DROP TABLE IF EXISTS " + COMMENTS_TABLE);

            // create fresh books table
            this.onCreate(db);
        }
    }


    private static final String KEY_ID = "id";
    private static final String KEY_COMMENT_TEXT = "KEY_COMMENT_TEXT";

    public void addItem(long phoneID, String comment) {
        Log.d(Constants.LOGGER_TAG, "add saved-offer");
        // 1. get reference to writable DB
        SQLiteDatabase db = this.getWritableDatabase();

        // 2. create ContentValues to add key "column"/value
        ContentValues values = new ContentValues();
        values.put(KEY_ID, phoneID);
        values.put(KEY_COMMENT_TEXT, comment);

        // 3. insert
        long newRowId = db.insertWithOnConflict(COMMENTS_TABLE, KEY_ID, values,
                SQLiteDatabase.CONFLICT_REPLACE);

        // 4. close
        db.close();
    }
}

但我收到此错误：即使重新安装我的应用程序

Process: com.example.stopcall.app, PID: 4720
android.database.sqlite.SQLiteException: no such table: COMMENTS_TABLE (code 1): , while compiling: INSERT OR REPLACE  INTO COMMENTS_TABLE(id,KEY_COMMENT_TEXT) VALUES (?,?)
        at android.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
        at android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:1113)
        at android.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:690)
        at android.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
        at android.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
        at android.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
        at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1601)
        at com.example.stopcall.app.dal.CommentDal.addItem(CommentDal.java:69)
        at com.example.stopcall.app.ItemDetailFragment$2.onClick(ItemDetailFragment.java:111)

Answer 1

您有两个SQLiteOpenHelper使用相同的数据库名称。每个数据库文件只使用一个辅助类。

数据库由一个帮助程序设置，而另一个帮助程序的生命周期回调将不会被调用，因为数据库已经存在。

Answer 2

你有两个不同的类，它们都扩展了SQLiteOpenHelper，碰巧拥有相同的数据库名称和版本。但Android并不知道。第一次访问PhoneDal时，它会创建数据库。当您访问CommentDal时，Android会注意到您已经拥有一个具有该名称和版本的数据库，因此它不会调用Comment Dal的onCreate，并且永远不会创建注释表。

你真的应该只有一个Dal用几种方法来添加手机并添加评论。

无法使用外键插入记录（android sqlite）

2 个答案: