Question

DatabaseHelper

public class DatabaseHelper extends SQLiteOpenHelper
{
public static final  String DBNAME = "sample.sql";
public static final String DBLOCATION = null;/*"/data/data/com.example.final_view.database/databases/"*/
public static final int DATABASE_VERSION = 3;
public static final String TABLE_NAME = "sample";
public static final String S_BUSSTOP_ID="BUSSTOP_ID";
public static final String S_BUSSTOP_NAME="BUSSTOP_NAME";
public static final String S_NAME_E="NAME_E";
public static final String S_LONGITUDE="LONGITUDE";
public static final String S_LATITUDE="LATITUDE";
public static final String S_ARS_ID="ARS_ID";
public static final String S_NEXT_BUS="NEXT_BUS";
public static final String S_NUM="NUM";
public static final String S_STATION_LIST_ID="STATION_LIST_ID";

private Context mContext;
private SQLiteDatabase mDatabase;
public DatabaseHelper (Context context)
{
    super(context, DBNAME, null, DATABASE_VERSION);
    Log.d("Database Operations", "Database created");
    this.mContext = context;
}

@Override
public void onCreate(SQLiteDatabase db)
{
    db.execSQL('CREATE TABLE' + TABLE_NAME + '('+S_BUSSTOP_ID + 'INTEGER'+S_BUSSTOP_NAME+'TEXT'+S_NAME_E+"TEXT"+S_ARS_ID+
            'TEXT'+S_LATITUDE+'TEXT'+S_LONGITUDE+'TEXT'+S_NEXT_BUS+'TEXT'+S_NUM+'TEXT'+S_STATION_LIST_ID+"TEXT);");

  }
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
    db.execSQL("DROP TABLE IF EXISTS" + TABLE_NAME);
    onCreate(db);
}
public  void openDatabase()
{
    String dbPath = mContext.getDatabasePath(DBNAME).getPath();
    if (mDatabase != null && mDatabase.isOpen())
    {
        return;
    }
    mDatabase = SQLiteDatabase.openDatabase(dbPath, null, SQLiteDatabase.OPEN_READWRITE);
}

    //db종료
public  void closeDatabase()
{
    if (mDatabase!=null)
    {
        mDatabase.close();
    }
}
//Method 값입력
public List<Busstation> getListProduct()
{
    Busstation busstation = null;
    List<Busstation> busstationList = new ArrayList<>();
    openDatabase();
    Cursor cursor = mDatabase.rawQuery('SELECT * FROM sample',null);// 여기 부분에서 에러가 나오는 부분입니다. sample.sql table 이름과 일치하게 해도 오류가 뜹니다.....         cursor.moveToFirst();
    while (!cursor.isAfterLast())
    {
        busstation =new Busstation(cursor.getInt(0), cursor.getString(1),cursor.getString(2),cursor.getString(3),cursor.getString(4),cursor.getString(5),cursor.getString(6),cursor.getString(7),cursor.getString(8));
        busstationList.add(busstation);
        cursor.moveToNext();
    }
    cursor.close();
    closeDatabase();
return busstationList;
}

}

MainActivity

public class MainActivity extends AppCompatActivity {

private ListView lvProduct;
private ListProductAdapter adapter;
private List<Busstation> mBusstationList;
private DatabaseHelper mDBHelper;

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

    //Process in onCreate
    lvProduct = (ListView)findViewById(R.id.listView_station);
    mDBHelper = new DatabaseHelper(this);

    //check exists database
    File database = getApplicationContext().getDatabasePath(DatabaseHelper.DBNAME);
    if (false == database.exists())
    {
        mDBHelper.getReadableDatabase();
        //copy DB
        if(copyDatabase(this))
        {
            Toast.makeText(this,"Copy database success", Toast.LENGTH_SHORT).show();
        }else
        {
            Toast.makeText(this,"Copy data error", Toast.LENGTH_SHORT).show();
            return;
        }
    }

    //GEt product list in db when db exists
    mBusstationList = mDBHelper.getListProduct();
    //Init adapter
    adapter = new ListProductAdapter(this, mBusstationList);
    //Set adapter for listview
    lvProduct.setAdapter(adapter);

    // note: need to use multithread for Large DB

 }

//create method copy database
private boolean copyDatabase(Context context)
{
    try
    {
        InputStream inputStream = context.getAssets().open(DatabaseHelper.DBNAME);
        String outFileName = DatabaseHelper.DBLOCATION + DatabaseHelper.DBNAME;
        OutputStream outputStream = new FileOutputStream(outFileName);
        byte[]buff = new byte[1024];
        int length = 0;
        while((length=inputStream.read(buff))>0)
        {
            outputStream.write(buff, 0, length);
        }
        outputStream.flush();
        outputStream.close();
        Log.w("MainActivity","DB copied");
        return  true;
    }catch (Exception e)
    {
        e.printStackTrace();
        return false;
    }

}
}
mBusstationList = mDBHelper.getListProduct(); 이부분에서 오류가 뜹니다!!
************************오류 내용 입니다*****************************

错误：

07-22 06:45:56.230 19094-19094/com.example.final_view D/Database Operations: Database created
07-22 06:45:56.241 19094-19094/com.example.final_view E/SQLiteLog: (1) no such table: sample
07-22 06:45:56.241 19094-19094/com.example.final_view D/AndroidRuntime: Shutting down VM
07-22 06:45:56.246 19094-19094/com.example.final_view E/AndroidRuntime: FATAL EXCEPTION: main
                                                                        Process: com.example.final_view, PID: 19094
                                                                        java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.final_view/com.example.final_view.MainActivity}: android.database.sqlite.SQLiteException: no such table: sample (code 1): , while compiling: SELECT * FROM sample

Answer 1

该表根本没有创建，因为您使用的表创建命令完全错误：

db.execSQL('CREATE TABLE' + TABLE_NAME + '('+S_BUSSTOP_ID + 'INTEGER'+S_BUSSTOP_NAME+'TEXT'+S_NAME_E+"TEXT"+S_ARS_ID+   'TEXT'+S_LATITUDE+'TEXT'+S_LONGITUDE+'TEXT'+S_NEXT_BUS+'TEXT'+S_NUM+'TEXT'+S_STATION_LIST_ID+"TEXT);");

0 - '必须为"
1 - 您错过空格以将列名与其数据类型分开 2 - 表名也必须分开 3 - 您在列定义之间错过了逗号。

这是正确的版本：

db.execSQL("CREATE TABLE " + TABLE_NAME + " (" + S_BUSSTOP_ID + " INTEGER, " + S_BUSSTOP_NAME + " TEXT, " + S_NAME_E + " TEXT, " + S_ARS_ID +  " TEXT, " + S_LATITUDE + " TEXT, " + S_LONGITUDE + " TEXT, " + S_NEXT_BUS + " TEXT, " + S_NUM + " TEXT, " + S_STATION_LIST_ID + " TEXT)");

你也错过了这里的空间

db.execSQL("DROP TABLE IF EXISTS" + TABLE_NAME);

必须是

db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);

这个

Cursor cursor = mDatabase.rawQuery('SELECT * FROM sample',null);

必须是

Cursor cursor = mDatabase.rawQuery("SELECT * FROM sample", null);

E / SQLiteLog：（1）没有这样的表：样本

1 个答案: