Sqlite Create表不是Executing

Question

我正在尝试在我的Android应用程序中创建Sqlite数据库。我编写了以下类，但是当我执行Insert方法时，它会给出以下错误消息：

onButtonClick，我创建了Database类的对象

DBHelper dbHelper= new DBHelper(getApplicationContext());

dbHelper.insertRemainder(formData);

错误

android.database.sqlite.SQLiteException: no such table: remainders (code 1): ,
while compiling: INSERT INTO remainders(REMAINDER_NOTES,PRIORITY,DATETIME,REMAINDER_NAME) 
VALUES (?,?,?,?)

这是我的SqliteDatabaseConnection班级

public class DBHelper extends SQLiteOpenHelper {

private static final String DATABASE_NAME="remainderApp";
private static final String TABLE_NAME= "remainders";
private static final String ID= "ID";
private static final String REMAINDER_NAME= "REMAINDER_NAME";
private static final String REMAINDER_NOTES= "REMAINDER_NOTES";
private static final String DATETIME= "DATETIME";
private static final String PRIORITY = "PRIORITY";


private static final String CREATE_TABLE= " create table "+ TABLE_NAME + " ( "+ID+" INTEGER PRIMARY KEY AUTOINCREMENT, "+REMAINDER_NAME+" TEXT,  "
                            +   REMAINDER_NOTES +" TEXT, "+DATETIME+" DATE, "+PRIORITY+" TEXT  )";

private static final String DROP_TABLE= "DROP TABLE IF EXISTS"+ TABLE_NAME;
private Context context;
private SQLiteDatabase db = null;


public DBHelper(Context context) {
    super(context, DATABASE_NAME, null , 1);
    this.context= context;
}

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


@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    try{
        db.execSQL(DROP_TABLE);
        onCreate(db);
    } catch (SQLException e) {
        e.printStackTrace();
    }
}


//CRUD

public boolean insertRemainder(FormData formData){
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues values = new ContentValues();

    values.put(REMAINDER_NAME,formData.getRemainderName());
    values.put(REMAINDER_NOTES, formData.getRemainderNotes());
    values.put(DATETIME, formData.getDateTime() );
    values.put(PRIORITY, formData.getRemainderPriority());

    long id= db.insert(TABLE_NAME, null, values);
    Log.d("tableQuery", CREATE_TABLE);

    if(id > 0){
        return true;
    }else{
        return false;
    }

}

当我打印CREATE_TABLE变量时，它会打印以下查询。

  

创建表余数（ID INTEGER PRIMARY KEY AUTOINCREMENT，   REMAINDER_NAME TEXT，REMAINDER_NOTES TEXT，DATETIME DATE，PRIORITY   文字）