android.database.sqlite.SQLiteException : no such column: personname: , 同时编译 : SELECT id, personname FROM numbersTable

Question

我是 android 新手，我想将数据库中的数据获取到 textview。

但是它有错误我无法纠正这个问题。

请帮帮我。

这是数据库类

    public class blockornot1 {
     String TAG;
 private dbHelper1 ourHelper;
 private final Context ourContext;
 private SQLiteDatabase ourDatabese;

  public final static  String DATABASE_NAME1="databasename.db";
  public final String DATABASE_TABLE="numbersTable";
  public final String KEY_NAME="personname";
  public final String KEY_ID="id";
  public final int DATABASE_VERSION =2;


  public  class dbHelper1 extends SQLiteOpenHelper{

    public dbHelper1 (Context context) {
          super (context,DATABASE_NAME1,null,DATABASE_VERSION);
          }

    @Override
    public void onCreate(SQLiteDatabase db) {
    db.execSQL("CREATE TABLE "+ DATABASE_TABLE+ "("+KEY_ID+ " INTEGER PRIMARY KEY AUTOINCREMENT, "               
      + KEY_NAME + "TEXT NOT NULL);");
        Log.v(TAG, "creat");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
        onCreate(db);

    }

  }``

  public blockornot1(Context c){

      ourContext = c;
  }

  public blockornot1 open() throws SQLException{
      ourHelper= new dbHelper1(ourContext);
      ourDatabese= ourHelper.getWritableDatabase();
      return this;
  }

  public void close(){
      ourHelper.close();

  }

public long creatEntry(String inputtext) {
    // TODO Auto-generated method stub
    ContentValues cv= new ContentValues();
    cv.put(KEY_NAME, inputtext);
    Log.v(inputtext, "add to database");
    return ourDatabese.insert(DATABASE_TABLE, null, cv);

}

public String getData() {
    // TODO Auto-generated method stub
    String[] columns = new String[]{ KEY_ID, KEY_NAME };
    Cursor c=ourDatabese.query(DATABASE_TABLE, columns, null, null, null, null,   null);
    String result = "";
    int iRow = c.getColumnIndex(KEY_ID);
    int iName = c.getColumnIndex(KEY_NAME);
    for(c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){

        result= result + c.getString(iRow) + "   " + c.getString(iName) + "/n";
    }
    return result;
   }


     }

这是我的主课

      public class Mainclass extends Activity implements OnClickListener {
      EditText et;
  String TAG;
    public void onCreate(Bundle savedInstanceState) {
        Log.v(TAG,"onCreate");
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

       et=(EditText)findViewById(R.id.edittext1);
       Button bt=(Button)findViewById(R.id.button1);
        Button bt1=(Button)findViewById(R.id.button2view);
        bt.setOnClickListener(this);
        bt1.setOnClickListener(this);

    }

        public void onClick(View v) {

            switch (v.getId()) {
            case R.id.button1:
                boolean dididwork =true;
                try{
                 String inputtext=et.getText().toString();
                 blockornot1 entry= new blockornot1(Mainclass.this);
                 entry.open();
                 entry.creatEntry(inputtext);
                 entry.close();
                 Log.v(TAG," okkkkkkk hastaaaaaaa");
                break;}
                catch (Exception e){
                    String error=e.toString();
                    Dialog d= new Dialog(this);
                    d.setTitle("Heack ya!"); 
                            TextView t= new TextView(this);
                            t.setText(error);
                            d.setContentView(t);
                            d.show();
                    dididwork=false;

                }finally {
                if(dididwork){
                    Dialog d= new Dialog(this);
                    d.setTitle("Heack ya!"); 
                            TextView t= new   TextView(this);
                            t.setText("success");
                            d.setContentView(t);
                            d.show();

                }

                }

            case R.id.button2view:
                Intent i = new Intent("android.intent.action.SQLVIEW");  
                startActivity(i);
                break;

            }




                  }

这个类用于在 TextView 中显示数据库

   public class ShowDb extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.sqlview);
    TextView tv=(TextView)findViewById(R.id.textViewsqlview);
    blockornot1 info= new blockornot1(this);
    info.open();
    String data= info.getData();
    info.close();
    tv.setText(data);
}

Answer 1

我猜你在某个时候更改了表的创建语句，但在你增加数据库版本之前，你的应用程序不会自动执行任何更改。尝试将 DATABASE_VERSION 设置为 3。

添加

如果您要将数据库中的信息绑定(bind)到 ListView、Spinner 等，则应将 KEY_ID 更改为 _id。 (Android 对主键列的名称有讲究。)