错误：没有这样的表：在 Sqlite 数据库中插入数据时

Question

我正在尝试将数据插入sqlite Database。我正在关注YoutubeTutorial 来完成这项任务。

我编写了以下代码，它成功创建了Sqlite Database file，但是当我尝试插入数据时，它给了我错误消息。

我已经编写了以下代码。请指导我在这里做错了什么。

public class DatabaseHelper extends SQLiteOpenHelper {

    public static final String DATABASE_NAME="ep";  
    public static final String TABLE_NAME= "transactionsHistory";
    public static final String ID= "ID";
    public static final String MESSAGE= "MESSAGE";
    public static final String CREATE_TABLE= "create table "+ TABLE_NAME + " ( "+ID+" INTEGER PRIMARY KEY AUTO INCREMENT, "+MESSAGE+" TEXT)";
    public static final String DROP_TABLE= "DROP TABLE IF EXISTS"+ TABLE_NAME; 
    private Context context;


    public DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null , 1);
        SQLiteDatabase db= this.getWritableDatabase();
        this.context= context; 
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        try {
            db.execSQL(CREATE_TABLE);
        } catch (SQLException e) {                  
            e.printStackTrace();        
        }
  }

public void insertData(DatabaseHelper dbHelper , String Message){

    SQLiteDatabase db= dbHelper.getWritableDatabase();

    ContentValues contentValues= new ContentValues();
    contentValues.put(MESSAGE, Message);
    db.insert(TABLE_NAME, null, contentValues);

    Log.d("Insert Successfull ", "Value : "+Message + " :Data Inserted");
}

在 Activity 中调用 DB 类

public class SuccessActivity extends Activity {

    TextView successMessage;
    String failureMessage;
    DatabaseHelper myDb;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_success);

        myDb= new DatabaseHelper(this);

        myDb.insertData(myDb, "This is a Random Message ");

错误

08-11 13:16:46.883: I/SqliteDatabaseCpp(22338): sqlite returned: error code = 1, msg = no such table: transactionsHistory, db=/data/data/com.example.ep/databases/ep
08-11 13:16:46.903: E/SQLiteDatabase(22338): Error inserting MESSAGE=This is a Random Message 
08-11 13:16:46.903: E/SQLiteDatabase(22338): android.database.sqlite.SQLiteException: no such table: transactionsHistory: , while compiling: INSERT INTO transactionsHistory(MESSAGE) VALUES (?)
08-11 13:16:46.903: E/SQLiteDatabase(22338):    at android.database.sqlite.SQLiteCompiledSql.native_compile(Native Method)
08-11 13:16:46.903: E/SQLiteDatabase(22338):    at android.database.sqlite.SQLiteCompiledSql.<init>(SQLiteCompiledSql.java:68)

Answer 1

没有创建您的表，因为您的 create table 语句中有错误。 AUTO 和 INCREMENT 之间不应有空格 - 即应该是：

public static final String CREATE_TABLE= "create table "+ TABLE_NAME + " ( "+ID+" INTEGER PRIMARY KEY AUTOINCREMENT, "+MESSAGE+" TEXT)";