連線資料庫SQLite查詢一筆資料，方法2：使用SQLiteDatabase物件語法：db.query


注意：整個事件程式碼都必須放在
onCreate() 
{  
}
下面
   // Button元件的事件處理 - 查詢記錄
    public void button1_Click(View view) {
    	String[] colNames=new String[]{"欄位1","欄位2","欄位3"};    	
    	String str = "";    	
    	Cursor c = db.query(DATABASE_TABLE, colNames,null, null, null, null,null);
    	// 顯示欄位名稱
      	for (int i = 0; i < colNames.length; i++)
    		str += colNames[i] + "\t\t";
    	str += "\n";
    	c.moveToFirst();  // 第1筆
    	// 顯示欄位值
    	for (int i = 0; i < c.getCount(); i++) {
    		str += c.getString(c.getColumnIndex(colNames[0])) + "\t\t";
    		str += c.getString(1) + "\t\t"; //第2欄位
    		str += c.getString(2) + "\t\t";//第3欄位
		//.............如果還要顯示其它欄位，就要再複製上面一行
    		c.moveToNext();  // 下一筆
    	}
    	output.setText(str.toString());    	

    } //end of button1_Click()

..........................

範例：

import android.view.*;
import android.widget.*;
import android.content.ContentValues;
import android.database.Cursor;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;


public class MainActivity extends Activity {

    private SQLiteDatabase db;
    private MyDBHelper dbHelper;
    private static String DATABASE_TABLE = "資料表名稱";'

    private EditText ed1,ed2,ed3;
    private TextView output;
 

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
			
	 // 建立SQLiteOpenHelper物件
        dbHelper = new MyDBHelper(this);
        db = dbHelper.getWritableDatabase(); // 開啟資料庫
        // 取得TextView元件
        output = (TextView) findViewById(R.id.textView4);  	
		
    }//end of onCreate()


   // Button元件的事件處理 - 查詢記錄
    public void button1_Click(View view) {
    	String[] colNames=new String[]{"欄位1","欄位2","欄位3"};    	
    	String str = "";    	
    	Cursor c = db.query(DATABASE_TABLE, colNames,null, null, null, null,null);
    	// 顯示欄位名稱
      	for (int i = 0; i < colNames.length; i++)
    		str += colNames[i] + "\t\t";
    	str += "\n";
    	c.moveToFirst();  // 第1筆
    	// 顯示欄位值
    	for (int i = 0; i < c.getCount(); i++) {
    		str += c.getString(c.getColumnIndex(colNames[0])) + "\t\t";
    		str += c.getString(1) + "\t\t"; //第2欄位
    		str += c.getString(2) + "\t\t";//第3欄位
		//.............如果還要顯示其它欄位，就要再複製上面一行
    		c.moveToNext();  // 下一筆
    	}
    	output.setText(str.toString());    	

    } //end of button1_Click()



	
//連線資料庫SQLite，新增資料表	
	public class MyDBHelper extends SQLiteOpenHelper {
		private static final String DATABASE_NAME = "資料庫名稱";
		private static final int DATABASE_VERSION = 1;
		
		public MyDBHelper(Context context) {
			super(context, DATABASE_NAME, null, DATABASE_VERSION);
		}
		@Override
		public void onCreate(SQLiteDatabase db) {			
			//新增資料表
			//資料表名稱與欄位名稱，不要用中文名稱
			db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (_id integer primary key autoincrement, "
			           + "name text no null, price real no null, num real no null)");
		}
		@Override
		public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
			db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE );
	        onCreate(db);
		}
	} //end of MyDBHelper extends SQLiteOpenHelper ()